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published/20160429 Why and how I became a software engineer.md
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我成为软件工程师的原因和经历
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==========================================
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1989 年乌干达首都，坎帕拉。
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我明智的父母决定与其将我留在家里添麻烦，不如把我送到叔叔的办公室学学电脑。几天后，我和另外六、七个小孩，还有一台放置在课桌上的崭新电脑，一起置身于 21 层楼的一间狭小房屋中。很明显我们还不够格去碰那家伙。在长达三周无趣的 DOS 命令学习后，美好时光来到，终于轮到我来输 **copy doc.txt d:** 啦。
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那将文件写入五英寸软盘的奇怪的声音，听起来却像音乐般美妙。那段时间，这块软盘简直成为了我的至宝。我把所有可以拷贝的东西都放在上面了。然而，1989 年的乌干达，人们的生活十分“正统”，相比较而言，捣鼓电脑、拷贝文件还有格式化磁盘就称不上“正统”。于是我不得不专注于自己接受的教育，远离计算机科学，走入建筑工程学。
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之后几年里，我和同龄人一样，干过很多份工作也学到了许多技能。我教过幼儿园的小朋友，也教过大人如何使用软件，在服装店工作过，还在教堂中担任过引座员。在我获取堪萨斯大学的学位时，我正在技术管理员的手下做技术助理，听上去比较神气，其实也就是搞搞学生数据库而已。
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当我 2007 年毕业时，计算机技术已经变得不可或缺。建筑工程学的方方面面都与计算机科学深深的交织在一起，所以我们不经意间学了些简单的编程知识。我对于这方面一直很着迷，但我不得不成为一位“正统”的工程师，由此我发展了一项秘密的私人爱好：写科幻小说。
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在我的故事中，我以我笔下的女主角的形式存在。她们都是编程能力出众的科学家，总是卷入冒险，并用自己的技术发明战胜那些渣渣们，有时甚至要在现场发明新方法。我提到的这些“新技术”，有的是基于真实世界中的发明，也有些是从科幻小说中读到的。这就意味着我需要了解这些技术的原理，而且我的研究使我关注了许多有趣的 reddit 版块和电子杂志。
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### 开源：巨大的宝库
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那几周在 DOS 命令上花费的经历对我影响巨大，我在一些非专业的项目上耗费心血，并占据了宝贵的学习时间。Geocities 刚向所有 Yahoo! 用户开放时，我就创建了一个网站，用于发布一些用小型数码相机拍摄的个人图片。我建立多个免费网站，帮助家人和朋友解决一些他们所遇到的电脑问题，还为教堂搭建了一个图书馆数据库。
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这意味着，我需要一直研究并尝试获取更多的信息，使它们变得更棒。互联网上帝保佑我，让开源进入我的视野。突然之间，30 天试用期和 license 限制对我而言就变成了过去式。我可以完全不受这些限制，继续使用 GIMP、Inkscape 和 OpenOffice。
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### 是正经做些事情的时候了
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我很幸运，有商业伙伴喜欢我的经历。她也是个想象力丰富的人，期待更高效、更便捷的互联世界。我们根据我们以往成功道路中经历的弱点制定了解决方案，但执行却成了一个问题。我们都缺乏给产品带来活力的能力，每当我们试图将想法带到投资人面前时，这表现的尤为突出。
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我们需要学习编程。于是 2015 年夏末，我们来到 Holberton 学校。那是一所座落于旧金山，由社区推进，基于项目教学的学校。
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一天早晨我的商业伙伴来找我，以她独有的方式（每当她有疯狂想法想要拉我入伙时），进行一场对话。
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**Zee**: Gloria，我想和你说点事，在你说“不”前能先听我说完吗？
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**Me**: 不行。
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**Zee**: 为做全栈工程师，咱们申请上一所学校吧。
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**Me**: 什么？
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**Zee**: 就是这，看！就是这所学校，我们要申请这所学校来学习编程。
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**Me**: 我不明白。我们不是正在网上学 Python 和…
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**Zee**: 这不一样。相信我。
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**Me**: 那…
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**Zee**: 这就是不信任我了。
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**Me**: 好吧 … 给我看看。
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### 抛开偏见
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我读到的和我们在网上看的的似乎很相似。这简直太棒了，以至于让人觉得不太真实，但我们还是决定尝试一下，全力以赴，看看结果如何。
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要成为学生，我们需要经历四步选择，不过选择的依据仅仅是天赋和动机，而不是学历和编程经历。筛选便是课程的开始，通过它我们开始学习与合作。
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根据我和我伙伴的经验， Holberton 学校的申请流程比其他的申请流程有趣太多了，就像场游戏。如果你完成了一项挑战，就能通往下一关，在那里有别的有趣的挑战正等着你。我们创建了 Twitter 账号，在 Medium 上写博客，为创建网站而学习 HTML 和 CSS， 打造了一个充满活力的在线社区，虽然在此之前我们并不知晓有谁会来。
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在线社区最吸引人的就是大家有多种多样的使用电脑的经验，而背景和性别不是社区创始人（我们私下里称他们为“The Trinity”）做出选择的因素。大家只是喜欢聚在一块儿交流。我们都行进在通过学习编程来提升自己计算机技术的旅途上。
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相较于其他的的申请流程，我们不需要泄露很多的身份信息。就像我的伙伴，她的名字里看不出她的性别和种族。直到最后一个步骤，在视频聊天的时候， The Trinity 才知道她是一位有色人种女性。迄今为止，促使她达到这个级别的只是她的热情和才华。肤色和性别并没有妨碍或者帮助到她。还有比这更酷的吗？
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获得录取通知书的晚上，我们知道生活将向我们的梦想转变。2016 年 1 月 22 日，我们来到巴特瑞大街 98 号，去见我们的同学们 [Hippokampoiers][2]，这是我们的初次见面。很明显，在见面之前，“The Trinity”已经做了很多工作，聚集了一批形形色色的人，他们充满激情与热情，致力于成长为全栈工程师。
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这所学校有种与众不同的体验。每天都是向某一方面编程的一次竭力的冲锋。交给我们的工程，并不会有很多指导，我们需要使用一切可以使用的资源找出解决方案。[Holberton 学校][1] 认为信息来源相较于以前已经大大丰富了。MOOC（大型开放式课程）、教程、可用的开源软件和项目，以及线上社区等等，为我们完成项目提供了足够的知识。加之宝贵的导师团队来指导我们制定解决方案，这所学校变得并不仅仅是一所学校；我们已经成为了求学者的团体。任何对软件工程感兴趣并对这种学习方法感兴趣的人，我都强烈推荐这所学校。在这里的经历会让人有些悲喜交加，但是绝对值得。
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### 开源问题
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我最早使用的开源系统是 [Fedora][3]，一个 [Red Hat][4] 赞助的项目。与 一名IRC 成员交流时，她推荐了这款免费的操作系统。 虽然在此之前，我还未独自安装过操作系统，但是这激起了我对开源的兴趣和日常使用计算机时对开源软件的依赖性。我们提倡为开源贡献代码，创造并使用开源的项目。我们的项目就在 Github 上，任何人都可以使用或是向它贡献出自己的力量。我们也会使用或以自己的方式为一些既存的开源项目做出贡献。在学校里，我们使用的大部分工具是开源的，例如 Fedora、[Vagrant][5]、[VirtualBox][6]、[GCC][7] 和 [Discourse][8]，仅举几例。
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在向软件工程师行进的路上，我始终憧憬着有朝一日能为开源社区做出一份贡献，能与他人分享我所掌握的知识。
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### 多样性问题
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站在教室里，和 29 位求学者交流心得，真是令人陶醉。学员中 40% 是女性， 44% 是有色人种。当你是一位有色人种且为女性，并身处于这个以缺乏多样性而著名的领域时，这些数字就变得非常重要了。这是高科技圣地麦加上的绿洲，我到达了。
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想要成为一个全栈工程师是十分困难的，你甚至很难了解这意味着什么。这是一条充满挑战但又有丰富回报的旅途。科技推动着未来飞速发展，而你也是美好未来很重要的一部分。虽然媒体在持续的关注解决科技公司的多样化的问题，但是如果能认清自己，清楚自己的背景，知道自己为什么想成为一名全栈工程师，你便能在某一方面迅速成长。
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不过可能最重要的是，告诉大家，女性在计算机的发展史上扮演过多么重要的角色，以帮助更多的女性回归到科技界，而且在给予就业机会时，不会因性别等因素而感到犹豫。女性的才能将会共同影响科技的未来，以及整个世界的未来。
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------------------------------------------------------------------------------
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via: https://opensource.com/life/16/4/my-open-source-story-gloria-bwandungi
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作者：[Gloria Bwandungi][a]
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译者：[martin2011qi](https://github.com/martin2011qi)
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校对：[jasminepeng](https://github.com/jasminepeng)
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本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创翻译，[Linux中国](https://linux.cn/) 荣誉推出
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[a]:https://opensource.com/users/nappybrain
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[1]: https://www.holbertonschool.com/
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[2]: https://twitter.com/hippokampoiers
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[3]: https://en.wikipedia.org/wiki/Fedora_(operating_system)
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[4]: https://www.redhat.com/
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[5]: https://www.vagrantup.com/
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[6]: https://www.virtualbox.org/
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[7]: https://gcc.gnu.org/
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[8]: https://www.discourse.org/
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@ -0,0 +1,58 @@
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为满足当今和未来 IT 需求，培训员工还是雇佣新人？
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================================================================
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在数字化时代，由于 IT 工具不断更新，技术公司紧随其后，对 IT 技能的需求也不断变化。对于企业来说，寻找和雇佣那些拥有令人垂涎能力的创新人才，是非常不容易的。同时，培训内部员工来使他们接受新的技能和挑战，需要一定的时间，而时间要求常常是紧迫的。
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[Sandy Hill][1] 对 IT 涉及到的多项技术都很熟悉。她作为 [Pegasystems][2] 项目的 IT 总监，负责多个 IT 团队，从应用的部署到数据中心的运营都要涉及。更重要的是，Pegasystems 开发帮助销售、市场、服务以及运营团队流水化操作，以及客户联络的应用。这意味着她需要掌握使用 IT 内部资源的最佳方法，面对公司客户遇到的 IT 挑战。
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**TEP（企业家项目）：这些年你是如何调整培训重心的？**
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**Hill**：在过去的几年中，我们经历了爆炸式的发展，现在我们要实现更多的全球化进程。因此，培训目标是确保每个人都在同一起跑线上。
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我们主要的关注点在培养员工使用新产品和工具上，这些新产品和工具能够推动创新，提高工作效率。例如，我们使用了之前没有的资产管理系统。因此我们需要为全部员工做培训，而不是雇佣那些已经知道该产品的人。当我们正在发展的时候，我们也试图保持紧张的预算和稳定的职员总数。所以，我们更愿意在内部培训而不是雇佣新人。
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**TEP：说说培训方法吧，怎样帮助你的员工发展他们的技能？**
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**Hill**：我要求每一位员工制定一个技术性的和非技术性的训练目标。这作为他们绩效评估的一部分。他们的技术性目标需要与他们的工作职能相符，非技术岗目标则随意，比如着重发展一项软技能，或是学一些专业领域之外的东西。我每年对职员进行一次评估，看看差距和不足之处，以使团队保持全面发展。
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**TEP：你的训练计划能够在多大程度上减轻招聘工作量, 保持职员的稳定性？**
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**Hill**：使我们的职员保持学习新技术的兴趣，可以让他们不断提高技能。让职员知道我们重视他们并且让他们在擅长的领域成长和发展，以此激励他们。
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**TEP：你们发现哪些培训是最有效的？**
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**HILL**：我们使用几种不同的培训方法，认为效果很好。对新的或特殊的项目，我们会由供应商提供培训课程，作为项目的一部分。要是这个方法不能实现，我们将进行脱产培训。我们也会购买一些在线的培训课程。我也鼓励职员每年参加至少一次会议，以了解行业的动向。
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**TEP：哪些技能需求，更适合雇佣新人而不是培训现有员工？**
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**Hill**：这和项目有关。最近有一个项目，需要使用 OpenStack，而我们根本没有这方面的专家。所以我们与一家从事这一领域的咨询公司合作。我们利用他们的专业人员运行该项目，并现场培训我们的内部团队成员。让内部员工学习他们需要的技能，同时还要完成他们的日常工作，是一项艰巨的任务。
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顾问帮助我们确定我们需要的员工人数。这样我们就可以对员工进行评估，看是否存在缺口。如果存在人员上的缺口，我们还需要额外的培训或是员工招聘。我们也确实雇佣了一些合同工。另一个选择是对一些全职员工进行为期六至八周的培训，但我们的项目模式不容许这么做。
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**TEP：最近雇佣的员工，他们的那些技能特别能够吸引到你？**
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**Hill**：在最近的招聘中，我更看重软技能。除了扎实的技术能力外，他们需要能够在团队中进行有效的沟通和工作，要有说服他人，谈判和解决冲突的能力。
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IT 人常常独来独往，不擅社交。然而如今IT 与整个组织结合越来越紧密，为其他业务部门提供有用的更新和状态报告的能力至关重要，可展示 IT 部门存在的重要性。
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--------------------------------------------------------------------------------
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via: https://enterprisersproject.com/article/2016/6/training-vs-hiring-meet-it-needs-today-and-tomorrow
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||||
|
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作者：[Paul Desmond][a]
|
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译者：[Cathon](https://github.com/Cathon)
|
||||
校对：[jasminepeng](https://github.com/jasminepeng)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
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[a]: https://enterprisersproject.com/user/paul-desmond
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[1]: https://enterprisersproject.com/user/sandy-hill
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[2]: https://www.pega.com/pega-can?&utm_source=google&utm_medium=cpc&utm_campaign=900.US.Evaluate&utm_term=pegasystems&gloc=9009726&utm_content=smAXuLA4U|pcrid|102822102849|pkw|pegasystems|pmt|e|pdv|c|
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@ -1,9 +1,11 @@
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小模块的开销
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JavaScript 小模块的开销
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====
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||||
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大约一年之前，我在将一个大型 JavaScript 代码库重构为小模块时发现了 Browserify 和 Webpack 中一个令人沮丧的事实：
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更新（2016/10/30）：我写完这篇文章之后，我在[这个基准测试中发了一个错误](https://github.com/nolanlawson/cost-of-small-modules/pull/8)，会导致 Rollup 比它预期的看起来要好一些。不过，整体结果并没有明显的不同（Rollup 仍然击败了 Browserify 和 Webpack，虽然它并没有像 Closure 十分好），所以我只是更新了图表。该基准测试包括了 [RequireJS 和 RequireJS Almond 打包器](https://github.com/nolanlawson/cost-of-small-modules/pull/5)，所以文章中现在也包括了它们。要看原始帖子，可以查看[历史版本](https://web.archive.org/web/20160822181421/https://nolanlawson.com/2016/08/15/the-cost-of-small-modules/)。
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> “代码越模块化，代码体积就越大。”- Nolan Lawson
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||||
大约一年之前，我在将一个大型 JavaScript 代码库重构为更小的模块时发现了 Browserify 和 Webpack 中一个令人沮丧的事实：
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> “代码越模块化，代码体积就越大。:< ”- Nolan Lawson
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||||
过了一段时间，Sam Saccone 发布了一些关于 [Tumblr][1] 和 [Imgur][2] 页面加载性能的出色的研究。其中指出：
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@ -15,9 +17,9 @@
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||||
|
||||
一个页面中包含的 JavaScript 脚本越多，页面加载也将越慢。庞大的 JavaScript 包会导致浏览器花费更多的时间去下载、解析和执行，这些都将加长载入时间。
|
||||
|
||||
即使当你使用如 Webpack [code splitting][3]、Browserify [factor bundles][4] 等工具将代码分解为多个包，时间的花费也仅仅是被延迟到页面生命周期的晚些时候。JavaScript 迟早都将有一笔开销。
|
||||
即使当你使用如 Webpack [code splitting][3]、Browserify [factor bundles][4] 等工具将代码分解为多个包，该开销也仅仅是被延迟到页面生命周期的晚些时候。JavaScript 迟早都将有一笔开销。
|
||||
|
||||
此外，由于 JavaScript 是一门动态语言，同时流行的 [CommonJS][5] 模块也是动态的，所以这就使得在最终分发给用户的代码中剔除无用的代码变得异常困难。譬如你可能只使用到 jQuery 中的 $.ajax，但是通过载入 jQuery 包，你将以整个包为代价。
|
||||
此外，由于 JavaScript 是一门动态语言，同时流行的 [CommonJS][5] 模块也是动态的，所以这就使得在最终分发给用户的代码中剔除无用的代码变得异常困难。譬如你可能只使用到 jQuery 中的 $.ajax，但是通过载入 jQuery 包，你将付出整个包的代价。
|
||||
|
||||
JavaScript 社区对这个问题提出的解决办法是提倡 [小模块][6] 的使用。小模块不仅有许多 [美好且实用的好处][7] 如易于维护，易于理解，易于集成等，而且还可以通过鼓励包含小巧的功能而不是庞大的库来解决之前提到的 jQuery 的问题。
|
||||
|
||||
@ -66,7 +68,7 @@ $ browserify node_modules/qs | browserify-count-modules
|
||||
|
||||
顺带一提，我写过的最大的开源站点 [Pokedex.org][21] 包含了 4 个包，共 311 个模块。
|
||||
|
||||
让我们先暂时忽略这些 JavaScript 包的实际大小，我认为去探索一下一定数量的模块本身开销会事一件有意思的事。虽然 Sam Saccone 的文章 [“2016 年 ES2015 转译的开销”][22] 已经广为流传，但是我认为他的结论还未到达足够深度，所以让我们挖掘的稍微再深一点吧。
|
||||
让我们先暂时忽略这些 JavaScript 包的实际大小，我认为去探索一下一定数量的模块本身开销会是一件有意思的事。虽然 Sam Saccone 的文章 [“2016 年 ES2015 转译的开销”][22] 已经广为流传，但是我认为他的结论还未到达足够深度，所以让我们挖掘的稍微再深一点吧。
|
||||
|
||||
### 测试环节！
|
||||
|
||||
@ -86,13 +88,13 @@ console.log(total)
|
||||
module.exports = 1
|
||||
```
|
||||
|
||||
我测试了五种打包方法：Browserify, 带 [bundle-collapser][24] 插件的 Browserify, Webpack, Rollup 和 Closure Compiler。对于 Rollup 和 Closure Compiler 我使用了 ES6 模块，而对于 Browserify 和 Webpack 则用的 CommonJS，目的是为了不涉及其各自缺点而导致测试的不公平（由于它们可能需要做一些转译工作，如 Babel 一样，而这些工作将会增加其自身的运行时间）。
|
||||
我测试了五种打包方法：Browserify、带 [bundle-collapser][24] 插件的 Browserify、Webpack、Rollup 和 Closure Compiler。对于 Rollup 和 Closure Compiler 我使用了 ES6 模块，而对于 Browserify 和 Webpack 则用的是 CommonJS，目的是为了不涉及其各自缺点而导致测试的不公平（由于它们可能需要做一些转译工作，如 Babel 一样，而这些工作将会增加其自身的运行时间）。
|
||||
|
||||
为了更好地模拟一个生产环境，我将带 -mangle 和 -compress 参数的 Uglify 用于所有的包，并且使用 gzip 压缩后通过 GitHub Pages 用 HTTPS 协议进行传输。对于每个包，我一共下载并执行 15 次，然后取其平均值，并使用 performance.now() 函数来记录载入时间（未使用缓存）与执行时间。
|
||||
为了更好地模拟一个生产环境，我对所有的包采用带 `-mangle` 和 `-compress` 参数的 `Uglify` ，并且使用 gzip 压缩后通过 GitHub Pages 用 HTTPS 协议进行传输。对于每个包，我一共下载并执行 15 次，然后取其平均值，并使用 `performance.now()` 函数来记录载入时间（未使用缓存）与执行时间。
|
||||
|
||||
### 包大小
|
||||
|
||||
在我们查看测试结果之前，我们有必要先来看一眼我们要测试的包文件。一下是每个包最小处理后但并未使用 gzip 压缩时的体积大小（单位：Byte）：
|
||||
在我们查看测试结果之前，我们有必要先来看一眼我们要测试的包文件。以下是每个包最小处理后但并未使用 gzip 压缩时的体积大小（单位：Byte）：
|
||||
|
||||
| | 100 个模块 | 1000 个模块 | 5000 个模块 |
|
||||
| --- | --- | --- | --- |
|
||||
@ -110,7 +112,7 @@ module.exports = 1
|
||||
| rollup | 300 | 2145 | 11510 |
|
||||
| closure | 302 | 2140 | 11789 |
|
||||
|
||||
Browserify 和 Webpack 的工作方式是隔离各个模块到各自的函数空间，然后声明一个全局载入器，并在每次 require() 函数调用时定位到正确的模块处。下面是我们的 Browserify 包的样子：
|
||||
Browserify 和 Webpack 的工作方式是隔离各个模块到各自的函数空间，然后声明一个全局载入器，并在每次 `require()` 函数调用时定位到正确的模块处。下面是我们的 Browserify 包的样子：
|
||||
|
||||
```
|
||||
(function e(t,n,r){function s(o,u){if(!n[o]){if(!t[o]){var a=typeof require=="function"&&require;if(!u&&a)return a(o,!0);if(i)return i(o,!0);var f=new Error("Cannot find module '"+o+"'");throw f.code="MODULE_NOT_FOUND",f}var l=n[o]={exports:{}};t[o][0].call(l.exports,function(e){var n=t[o][1][e];return s(n?n:e)},l,l.exports,e,t,n,r)}return n[o].exports}var i=typeof require=="function"&&require;for(var o=0;o
|
||||
@ -144,7 +146,7 @@ Browserify 和 Webpack 的工作方式是隔离各个模块到各自的函数空
|
||||
|
||||
在 100 个模块时，各包的差异是微不足道的，但是一旦模块数量达到 1000 个甚至 5000 个时，差异将会变得非常巨大。iPod Touch 在不同包上的差异并不明显，而对于具有一定年代的 Nexus 5 来说，Browserify 和 Webpack 明显耗时更多。
|
||||
|
||||
与此同时，我发现有意思的是 Rollup 和 Closure 的运行开销对于 iPod 而言几乎可以忽略，并且与模块的数量关系也不大。而对于 Nexus 5 来说，运行的开销并非完全可以忽略，但它们仍比 Browserify 或 Webpack 低很多。后者若未在几百毫秒内完成加载则将会占用主线程的好几帧的时间，这就意味着用户界面将冻结并且等待直到模块载入完成。
|
||||
与此同时，我发现有意思的是 Rollup 和 Closure 的运行开销对于 iPod 而言几乎可以忽略，并且与模块的数量关系也不大。而对于 Nexus 5 来说，运行的开销并非完全可以忽略，但 Rollup/Closure 仍比 Browserify/Webpack 低很多。后者若未在几百毫秒内完成加载则将会占用主线程的好几帧的时间，这就意味着用户界面将冻结并且等待直到模块载入完成。
|
||||
|
||||
值得注意的是前面这些测试都是在千兆网速下进行的，所以在网络情况来看，这只是一个最理想的状况。借助 Chrome 开发者工具，我们可以认为地将 Nexus 5 的网速限制到 3G 水平，然后来看一眼这对测试产生的影响（[查看表格][30]）：
|
||||
|
||||
@ -152,13 +154,13 @@ Browserify 和 Webpack 的工作方式是隔离各个模块到各自的函数空
|
||||
|
||||
一旦我们将网速考虑进来，Browserify/Webpack 和 Rollup/Closure 的差异将变得更为显著。在 1000 个模块规模（接近于 Reddit 1050 个模块的规模）时，Browserify 花费的时间比 Rollup 长大约 400 毫秒。然而 400 毫秒已经不是一个小数目了，正如 Google 和 Bing 指出的，亚秒级的延迟都会 [对用户的参与产生明显的影响][32] 。
|
||||
|
||||
还有一件事需要指出，那就是这个测试并非测量 100 个、1000 个或者 5000 个模块的每个模块的精确运行时间。因为这还与你对 require() 函数的使用有关。在这些包中，我采用的是对每个模块调用一次 require() 函数。但如果你每个模块调用了多次 require() 函数（这在代码库中非常常见）或者你多次动态调用 require() 函数（例如在子函数中调用 require() 函数），那么你将发现明显的性能退化。
|
||||
还有一件事需要指出，那就是这个测试并非测量 100 个、1000 个或者 5000 个模块的每个模块的精确运行时间。因为这还与你对 `require()` 函数的使用有关。在这些包中，我采用的是对每个模块调用一次 `require()` 函数。但如果你每个模块调用了多次 `require()` 函数（这在代码库中非常常见）或者你多次动态调用 `require()` 函数（例如在子函数中调用 `require()` 函数），那么你将发现明显的性能退化。
|
||||
|
||||
Reddit 的移动站点就是一个很好的例子。虽然该站点有 1050 个模块，但是我测量了它们使用 Browserify 的实际执行时间后发现比“1000 个模块”的测试结果差好多。当使用那台运行 Chrome 的 Nexus 5 时，我测出 Reddit 的 Browserify require() 函数耗时 2.14 秒。而那个“1000 个模块”脚本中的等效函数只需要 197 毫秒（在搭载 i7 处理器的 Surface Book 上的桌面版 Chrome，我测出的结果分别为 559 毫秒与 37 毫秒，虽然给出桌面平台的结果有些令人惊讶）。
|
||||
|
||||
这结果提示我们有必要对每个模块使用多个 require() 函数的情况再进行一次测试。不过，我并不认为这对 Browserify 和 Webpack 会是一个公平的测试，因为 Rollup 和 Closure 都会将重复的 ES6 库导入处理为一个的顶级变量声明，同时也阻止了顶层空间以外的其他区域的导入。所以根本上来说，Rollup 和 Closure 中一个导入和多个导入的开销是相同的，而对于 Browserify 和 Webpack，运行开销随 require() 函数的数量线性增长。
|
||||
这结果提示我们有必要对每个模块使用多个 `require()` 函数的情况再进行一次测试。不过，我并不认为这对 Browserify 和 Webpack 会是一个公平的测试，因为 Rollup 和 Closure 都会将重复的 ES6 库导入处理为一个的顶级变量声明，同时也阻止了顶层空间以外的其他区域的导入。所以根本上来说，Rollup 和 Closure 中一个导入和多个导入的开销是相同的，而对于 Browserify 和 Webpack，运行开销随 `require()` 函数的数量线性增长。
|
||||
|
||||
为了我们这个分析的目的，我认为最好假设模块的数量是性能的短板。而事实上，“5000 个模块”也是一个比“5000 个 require() 函数调用”更好的度量标准。
|
||||
为了我们这个分析的目的，我认为最好假设模块的数量是性能的短板。而事实上，“5000 个模块”也是一个比“5000 个 `require()` 函数调用”更好的度量标准。
|
||||
|
||||
### 结论
|
||||
|
||||
@ -168,11 +170,11 @@ Reddit 的移动站点就是一个很好的例子。虽然该站点有 1050 个
|
||||
|
||||
给出这些结果之后，我对 Closure Compiler 和 Rollup 在 JavaScript 社区并没有得到过多关注而感到惊讶。我猜测或许是因为（前者）需要依赖 Java，而（后者）仍然相当不成熟并且未能做到开箱即用（详见 [Calvin’s Metcalf 的评论][37] 中作的不错的总结）。
|
||||
|
||||
即使没有足够数量的 JavaScript 开发者加入到 Rollup 或 Closure 的队伍中，我认为 npm 包作者们也已准备好了去帮助解决这些问题。如果你使用 npm 安装 lodash，你将会发其现主要的导入是一个巨大的 JavaScript 模块，而不是你期望的 Lodash 的超模块（hyper-modular）特性（require('lodash/uniq')，require('lodash.uniq') 等等）。对于 PouchDB，我们做了一个类似的声明以 [使用 Rollup 作为预发布步骤][38]，这将产生对于用户而言尽可能小的包。
|
||||
即使没有足够数量的 JavaScript 开发者加入到 Rollup 或 Closure 的队伍中，我认为 npm 包作者们也已准备好了去帮助解决这些问题。如果你使用 npm 安装 lodash，你将会发其现主要的导入是一个巨大的 JavaScript 模块，而不是你期望的 Lodash 的超模块（hyper-modular）特性（`require('lodash/uniq')`，`require('lodash.uniq')` 等等）。对于 PouchDB，我们做了一个类似的声明以 [使用 Rollup 作为预发布步骤][38]，这将产生对于用户而言尽可能小的包。
|
||||
|
||||
同时，我创建了 [rollupify][39] 来尝试将这过程变得更为简单一些，只需拖动到已存在的 Browserify 工程中即可。其基本思想是在你自己的项目中使用导入（import）和导出（export）（可以使用 [cjs-to-es6][40] 来帮助迁移），然后使用 require() 函数来载入第三方包。这样一来，你依旧可以在你自己的代码库中享受所有模块化的优点，同时能导出一个适当大小的大模块来发布给你的用户。不幸的是，你依旧得为第三方库付出一些代价，但是我发现这是对于当前 npm 生态系统的一个很好的折中方案。
|
||||
|
||||
所以结论如下：一个大的 JavaScript 包比一百个小 JavaScript 模块要快。尽管这是事实，我依旧希望我们社区能最终发现我们所处的困境————提倡小模块的原则对开发者有利，但是对用户不利。同时希望能优化我们的工具，使得我们可以对两方面都有利。
|
||||
所以结论如下：**一个大的 JavaScript 包比一百个小 JavaScript 模块要快**。尽管这是事实，我依旧希望我们社区能最终发现我们所处的困境————提倡小模块的原则对开发者有利，但是对用户不利。同时希望能优化我们的工具，使得我们可以对两方面都有利。
|
||||
|
||||
### 福利时间！三款桌面浏览器
|
||||
|
||||
@ -205,15 +207,15 @@ Firefox 48 ([查看表格][45])
|
||||
|
||||
[![Nexus 5 (3G) RequireJS 结果][53]](https://nolanwlawson.files.wordpress.com/2016/08/2016-08-20-14_45_29-small_modules3-xlsx-excel.png)
|
||||
|
||||
|
||||
更新 3: 我写了一个 [optimize-js](http://github.com/nolanlawson/optimize-js) ，它会减少一些函数内的函数的解析成本。
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://nolanlawson.com/2016/08/15/the-cost-of-small-modules/?utm_source=javascriptweekly&utm_medium=email
|
||||
via: https://nolanlawson.com/2016/08/15/the-cost-of-small-modules/
|
||||
|
||||
作者：[Nolan][a]
|
||||
译者：[Yinr](https://github.com/Yinr)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
校对：[wxy](https://github.com/wxy)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
@ -0,0 +1,57 @@
|
||||
宽松开源许可证的崛起意味着什么
|
||||
====
|
||||
|
||||
为什么像 GNU GPL 这样的限制性许可证越来越不受青睐。
|
||||
|
||||
“如果你用了任何开源软件， 那么你软件的其他部分也必须开源。” 这是微软前 CEO 巴尔默 2001 年说的， 尽管他说的不对， 还是引发了人们对自由软件的 FUD （恐惧， 不确定和怀疑（fear, uncertainty and doubt））。 大概这才是他的意图。
|
||||
|
||||
对开源软件的这些 FUD 主要与开源许可有关。 现在有许多不同的许可证， 当中有些限制比其他的更严格（也有人称“更具保护性”）。 诸如 GNU 通用公共许可证 （GPL） 这样的限制性许可证使用了 copyleft 的概念。 copyleft 赋予人们自由发布软件副本和修改版的权力， 只要衍生工作保留同样的权力。 bash 和 GIMP 等开源项目就是使用了 GPL(v3)。 还有一个 AGPL（ Affero GPL） 许可证， 它为网络上的软件（如 web service）提供了 copyleft 许可。
|
||||
|
||||
这意味着， 如果你使用了这种许可的代码， 然后加入了你自己的专有代码， 那么在一些情况下， 整个代码， 包括你的代码也就遵从这种限制性开源许可证。 Ballmer 说的大概就是这类的许可证。
|
||||
|
||||
但宽松许可证不同。 比如， 只要保留版权声明和许可声明且不要求开发者承担责任， MIT 许可证允许任何人任意使用开源代码， 包括修改和出售。 另一个比较流行的宽松开源许可证是 Apache 许可证 2.0，它还包含了贡献者向用户提供专利授权相关的条款。 使用 MIT 许可证的有 JQuery、.NET Core 和 Rails ， 使用 Apache 许可证 2.0 的软件包括安卓， Apache 和 Swift。
|
||||
|
||||
两种许可证类型最终都是为了让软件更有用。 限制性许可证促进了参与和分享的开源理念， 使每一个人都能从软件中得到最大化的利益。 而宽松许可证通过允许人们任意使用软件来确保人们能从软件中得到最多的利益， 即使这意味着他们可以使用代码， 修改它， 据为己有，甚至以专有软件出售，而不做任何回报。
|
||||
|
||||
开源许可证管理公司黑鸭子软件的数据显示， 去年使用最多的开源许可证是限制性许可证 GPL 2.0，份额大约 25%。 宽松许可证 MIT 和 Apache 2.0 次之， 份额分别为 18% 和 16%， 再后面是 GPL 3.0, 份额大约 10%。 这样来看， 限制性许可证占 35%， 宽松许可证占 34%， 几乎是平手。
|
||||
|
||||
但这份当下的数据没有揭示发展趋势。黑鸭子软件的数据显示， 从 2009 年到 2015 年的六年间， MIT 许可证的份额上升了 15.7%， Apache 的份额上升了 12.4%。 在这段时期， GPL v2 和 v3 的份额惊人地下降了 21.4%。 换言之， 在这段时期里， 大量软件从限制性许可证转到宽松许可证。
|
||||
|
||||
这个趋势还在继续。 黑鸭子软件的[最新数据][1]显示， MIT 现在的份额为 26%， GPL v2 为 21%， Apache 2 为 16%， GPL v3 为 9%。 即 30% 的限制性许可证和 42% 的宽松许可证－－与前一年的 35% 的限制许可证和 34% 的宽松许可证相比， 发生了重大的转变。 对 GitHub 上使用许可证的[调查研究][2]证实了这种转变。 它显示 MIT 以压倒性的 45% 占有率成为最流行的许可证， 与之相比， GPL v2 只有 13%， Apache 11%。
|
||||
|
||||
|
||||
|
||||
### 引领趋势
|
||||
|
||||
从限制性许可证到宽松许可证，这么大的转变背后是什么呢？ 是公司害怕如果使用了限制性许可证的软件，他们就会像巴尔默说的那样，失去自己私有软件的控制权了吗？ 事实上， 可能就是如此。 比如， Google 就[禁用了 Affero GPL 软件][3]。
|
||||
|
||||
[Instructional Media + Magic][4] 的主席 Jim Farmer， 是一个教育开源技术的开发者。 他认为很多公司为避免法律问题而不使用限制性许可证。 “问题就在于复杂性。 许可证的复杂性越高， 被他人因为某行为而告上法庭的可能性越高。 高复杂性更可能带来诉讼”， 他说。
|
||||
|
||||
他补充说， 这种对限制性许可证的恐惧正被律师们驱动着， 许多律师建议自己的客户使用 MIT 或 Apache 2.0 许可证的软件， 并明确反对使用 Affero 许可证的软件。
|
||||
|
||||
他说， 这会对软件开发者产生影响， 因为如果公司都避开限制性许可证软件的使用，开发者想要自己的软件被使用， 就更会把新的软件使用宽松许可证。
|
||||
|
||||
但 SalesAgility（开源 SuiteCRM 背后的公司）的 CEO Greg Soper 认为这种到宽松许可证的转变也是由一些开发者驱动的。 “看看像 Rocket.Chat 这样的应用。 开发者本可以选择 GPL 2.0 或 Affero 许可证， 但他们选择了宽松许可证，” 他说。 “这样可以给这个应用最大的机会， 因为专有软件厂商可以使用它， 不会伤害到他们的产品， 且不需要把他们的产品也使用开源许可证。 这样如果开发者想要让第三方应用使用他的应用的话， 他有理由选择宽松许可证。”
|
||||
|
||||
Soper 指出， 限制性许可证致力于帮助开源项目获得成功，方式是阻止开发者拿了别人的代码、做了修改，但不把结果回报给社区。 “Affero 许可证对我们的产品健康发展很重要， 因为如果有人利用了我们的代码开发，做得比我们好， 却又不把代码回报回来， 就会扼杀掉我们的产品，” 他说。 “ 对 Rocket.Chat 则不同， 因为如果它使用 Affero， 那么它会污染公司的知识产权， 所以公司不会使用它。 不同的许可证有不同的使用案例。”
|
||||
|
||||
曾在 Gnome、OpenOffice 工作过，现在是 LibreOffice 的开源开发者的 Michael Meeks 同意 Jim Farmer 的观点，认为许多公司确实出于对法律的担心，而选择使用宽松许可证的软件。 “copyleft 许可证有风险， 但同样也有巨大的益处。 遗憾的是人们都听从律师的， 而律师只是讲风险， 却从不告诉你有些事是安全的。”
|
||||
|
||||
巴尔默发表他的错误言论已经过去 15 年了， 但它产生的 FUD 还是有影响－－即使从限制性许可证到宽松许可证的转变并不是他的目的。
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: http://www.cio.com/article/3120235/open-source-tools/what-the-rise-of-permissive-open-source-licenses-means.html
|
||||
|
||||
作者：[Paul Rubens][a]
|
||||
译者：[willcoderwang](https://github.com/willcoderwang)
|
||||
校对：[jasminepeng](https://github.com/jasminepeng)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]: http://www.cio.com/author/Paul-Rubens/
|
||||
[1]: https://www.blackducksoftware.com/top-open-source-licenses
|
||||
[2]: https://github.com/blog/1964-open-source-license-usage-on-github-com
|
||||
[3]: http://www.theregister.co.uk/2011/03/31/google_on_open_source_licenses/
|
||||
[4]: http://immagic.com/
|
||||
|
||||
@ -1,7 +1,7 @@
|
||||
在 Linux 上检测硬盘坏道和坏块
|
||||
在 Linux 上检测硬盘上的坏道和坏块
|
||||
===
|
||||
|
||||
让我们从定义坏道和坏块开始说起，它们是一块磁盘或闪存上不再能够被读写的部分，一般是由于磁盘表面特定的[物理损坏][7]或闪存晶体管失效导致的。
|
||||
让我们从坏道和坏块的定义开始说起，它们是一块磁盘或闪存上不再能够被读写的部分，一般是由于磁盘表面特定的[物理损坏][7]或闪存晶体管失效导致的。
|
||||
|
||||
随着坏道的继续积累，它们会对你的磁盘或闪存容量产生令人不快或破坏性的影响，甚至可能会导致硬件失效。
|
||||
|
||||
@ -13,7 +13,7 @@
|
||||
|
||||
### 在 Linux 上使用坏块工具检查坏道
|
||||
|
||||
坏块工具可以让用户扫描设备检查坏道或坏块。设备可以是一个磁盘或外置磁盘，由一个如 /dev/sdc 这样的文件代表。
|
||||
坏块工具可以让用户扫描设备检查坏道或坏块。设备可以是一个磁盘或外置磁盘，由一个如 `/dev/sdc` 这样的文件代表。
|
||||
|
||||
首先，通过超级用户权限执行 [fdisk 命令][5]来显示你的所有磁盘或闪存的信息以及它们的分区信息：
|
||||
|
||||
@ -24,9 +24,9 @@ $ sudo fdisk -l
|
||||
|
||||
[][4]
|
||||
|
||||
列出 Linux 文件系统分区
|
||||
*列出 Linux 文件系统分区*
|
||||
|
||||
然后用这个命令检查你的 Linux 硬盘上的坏道/坏块：
|
||||
然后用如下命令检查你的 Linux 硬盘上的坏道/坏块：
|
||||
|
||||
```
|
||||
$ sudo badblocks -v /dev/sda10 > badsectors.txt
|
||||
@ -35,15 +35,15 @@ $ sudo badblocks -v /dev/sda10 > badsectors.txt
|
||||
|
||||
[][3]
|
||||
|
||||
在 Linux 上扫描硬盘坏道
|
||||
*在 Linux 上扫描硬盘坏道*
|
||||
|
||||
上面的命令中，badblocks 扫描设备 /dev/sda10（记得指定你的实际设备），-v 选项让它显示操作的详情。另外，这里使用了输出重定向将操作结果重定向到了文件 badsectors.txt。
|
||||
上面的命令中，badblocks 扫描设备 `/dev/sda10`（记得指定你的实际设备），`-v` 选项让它显示操作的详情。另外，这里使用了输出重定向将操作结果重定向到了文件 `badsectors.txt`。
|
||||
|
||||
如果你在你的磁盘上发现任何坏道，卸载磁盘并像下面这样让系统不要将数据写入回报的扇区中。
|
||||
|
||||
你需要执行 e2fsck（针对 ext2/ext3/ext4 文件系统）或 fsck 命令，命令中还需要用到 badsectors.txt 文件和设备文件。
|
||||
你需要执行 `e2fsck`（针对 ext2/ext3/ext4 文件系统）或 `fsck` 命令，命令中还需要用到 `badsectors.txt` 文件和设备文件。
|
||||
|
||||
`-l` 选项告诉命令将指定文件名文件（badsectors.txt）中列出的扇区号码加入坏块列表。
|
||||
`-l` 选项告诉命令将在指定的文件 `badsectors.txt` 中列出的扇区号码加入坏块列表。
|
||||
|
||||
```
|
||||
------------ 针对 for ext2/ext3/ext4 文件系统 ------------
|
||||
@ -60,7 +60,7 @@ $ sudo fsck -l badsectors.txt /dev/sda10
|
||||
|
||||
这个方法对带有 S.M.A.R.T（Self-Monitoring, Analysis and Reporting Technology，自我监控分析报告技术）系统的现代磁盘（ATA/SATA 和 SCSI/SAS 硬盘以及固态硬盘）更加的可靠和高效。S.M.A.R.T 系统能够帮助检测，报告，以及可能记录它们的健康状况，这样你就可以找出任何可能出现的硬件失效。
|
||||
|
||||
你可以使用以下命令安装 smartmontools：
|
||||
你可以使用以下命令安装 `smartmontools`：
|
||||
|
||||
```
|
||||
------------ 在基于 Debian/Ubuntu 的系统上 ------------
|
||||
@ -71,7 +71,7 @@ $ sudo yum install smartmontools
|
||||
|
||||
```
|
||||
|
||||
安装完成之后，使用 smartctl 控制磁盘集成的 S.M.A.R.T 系统。你可以这样查看它的手册或帮助：
|
||||
安装完成之后，使用 `smartctl` 控制磁盘集成的 S.M.A.R.T 系统。你可以这样查看它的手册或帮助：
|
||||
|
||||
```
|
||||
$ man smartctl
|
||||
@ -79,7 +79,7 @@ $ smartctl -h
|
||||
|
||||
```
|
||||
|
||||
然后执行 smartctrl 命令并在命令中指定你的设备作为参数，以下命令包含了参数 `-H` 或 `--health` 以显示 SMART 整体健康自我评估测试结果。
|
||||
然后执行 `smartctrl` 命令并在命令中指定你的设备作为参数，以下命令包含了参数 `-H` 或 `--health` 以显示 SMART 整体健康自我评估测试结果。
|
||||
|
||||
```
|
||||
$ sudo smartctl -H /dev/sda10
|
||||
@ -88,7 +88,7 @@ $ sudo smartctl -H /dev/sda10
|
||||
|
||||
[][2]
|
||||
|
||||
检查 Linux 硬盘健康
|
||||
*检查 Linux 硬盘健康*
|
||||
|
||||
上面的结果指出你的硬盘很健康，近期内不大可能发生硬件失效。
|
||||
|
||||
@ -102,10 +102,8 @@ via: http://www.tecmint.com/check-linux-hard-disk-bad-sectors-bad-blocks/
|
||||
|
||||
|
||||
作者：[Aaron Kili][a]
|
||||
|
||||
译者：[alim0x](https://github.com/alim0x)
|
||||
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
校对：[wxy](https://github.com/wxy)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
@ -1,12 +1,13 @@
|
||||
# 如何在 Linux 中将文件编码转换为 UTF-8
|
||||
如何在 Linux 中将文件编码转换为 UTF-8
|
||||
===============
|
||||
|
||||
在这篇教程中，我们将解释字符编码的含义，然后给出一些使用命令行工具将使用某种字符编码的文件转化为另一种编码的例子。最后，我们将一起看一看如何在 Linux 下将使用各种字符编码的文件转化为 UTF-8 编码。
|
||||
|
||||
你可能已经知道，计算机是不会理解和存储字符、数字或者任何人类能够理解的东西的，除了二进制数据。一个二进制位只有两种可能的值，也就是 `0` 或 `1`，`真`或`假`，`对`或`错`。其它的任何事物，比如字符、数据和图片，必须要以二进制的形式来表现，以供计算机处理。
|
||||
你可能已经知道，计算机除了二进制数据，是不会理解和存储字符、数字或者任何人类能够理解的东西的。一个二进制位只有两种可能的值，也就是 `0` 或 `1`，`真`或`假`，`是`或`否`。其它的任何事物，比如字符、数据和图片，必须要以二进制的形式来表现，以供计算机处理。
|
||||
|
||||
简单来说，字符编码是一种可以指示电脑来将原始的 0 和 1 解释成实际字符的方式，在这些字符编码中，字符都可以用数字串来表示。
|
||||
简单来说，字符编码是一种可以指示电脑来将原始的 0 和 1 解释成实际字符的方式，在这些字符编码中，字符都以一串数字来表示。
|
||||
|
||||
字符编码方案有很多种，比如 ASCII, ANCI, Unicode 等等。下面是 ASCII 编码的一个例子。
|
||||
字符编码方案有很多种，比如 ASCII、ANCI、Unicode 等等。下面是 ASCII 编码的一个例子。
|
||||
|
||||
```
|
||||
字符 二进制
|
||||
@ -22,11 +23,9 @@ B 01000010
|
||||
$ file -i Car.java
|
||||
$ file -i CarDriver.java
|
||||
```
|
||||
[
|
||||
|
||||
][3]
|
||||
|
||||
|
||||
在 Linux 中查看文件的编码
|
||||
*在 Linux 中查看文件的编码*
|
||||
|
||||
iconv 工具的使用方法如下：
|
||||
|
||||
@ -34,25 +33,21 @@ iconv 工具的使用方法如下：
|
||||
$ iconv option
|
||||
$ iconv options -f from-encoding -t to-encoding inputfile(s) -o outputfile
|
||||
```
|
||||
|
||||
在这里，`-f` 或 `--from-code` 标明了输入编码，而 `-t` 或 `--to-encoding` 指定了输出编码。
|
||||
在这里，`-f` 或 `--from-code` 表明了输入编码，而 `-t` 或 `--to-encoding` 指定了输出编码。
|
||||
|
||||
为了列出所有已有编码的字符集，你可以使用以下命令：
|
||||
|
||||
```
|
||||
$ iconv -l
|
||||
```
|
||||
[
|
||||
|
||||
][2]
|
||||
|
||||
|
||||
列出所有已有编码字符集
|
||||
*列出所有已有编码字符集*
|
||||
|
||||
### 将文件从 ISO-8859-1 编码转换为 UTF-8 编码
|
||||
|
||||
下面，我们将学习如何将一种编码方案转换为另一种编码方案。下面的命令将会将 ISO-8859-1 编码转换为 UTF-8 编码。
|
||||
|
||||
Consider a file named `input.file` which contains the characters:
|
||||
考虑如下文件 `input.file`，其中包含这几个字符：
|
||||
|
||||
```
|
||||
@ -70,17 +65,15 @@ $ iconv -f ISO-8859-1 -t UTF-8//TRANSLIT input.file -o out.file
|
||||
$ cat out.file
|
||||
$ file -i out.file
|
||||
```
|
||||
[
|
||||
|
||||
][1]
|
||||
|
||||
|
||||
在 Linux 中将 ISO-8859-1 转化为 UTF-8
|
||||
*在 Linux 中将 ISO-8859-1 转化为 UTF-8*
|
||||
|
||||
注意：如果输出编码后面添加了 `//IGNORE` 字符串，那些不能被转换的字符将不会被转换，并且在转换后，程序会显示一条错误信息。
|
||||
|
||||
好，如果字符串 `//TRANSLIT` 被添加到了上面例子中的输出编码之后 (UTF-8//TRANSLIT)，待转换的字符会尽量采用形译原则。也就是说，如果某个字符在输出编码方案中不能被表示的话，它将会被替换为一个形状比较相似的字符。
|
||||
好，如果字符串 `//TRANSLIT` 被添加到了上面例子中的输出编码之后 (`UTF-8//TRANSLIT`)，待转换的字符会尽量采用形译原则。也就是说，如果某个字符在输出编码方案中不能被表示的话，它将会被替换为一个形状比较相似的字符。
|
||||
|
||||
而且，如果一个字符不在输出编码中，而且不能被形译，它将会在输出文件中被一个问号标记 `(?)` 代替。
|
||||
而且，如果一个字符不在输出编码中，而且不能被形译，它将会在输出文件中被一个问号标记 `?` 代替。
|
||||
|
||||
### 将多个文件转换为 UTF-8 编码
|
||||
|
||||
@ -88,13 +81,13 @@ $ file -i out.file
|
||||
|
||||
```
|
||||
#!/bin/bash
|
||||
# 将 values_here 替换为输入编码
|
||||
### 将 values_here 替换为输入编码
|
||||
FROM_ENCODING="value_here"
|
||||
# 输出编码 (UTF-8)
|
||||
### 输出编码 (UTF-8)
|
||||
TO_ENCODING="UTF-8"
|
||||
# 转换命令
|
||||
### 转换命令
|
||||
CONVERT=" iconv -f $FROM_ENCODING -t $TO_ENCODING"
|
||||
# 使用循环转换多个文件
|
||||
### 使用循环转换多个文件
|
||||
for file in *.txt; do
|
||||
$CONVERT "$file" -o "${file%.txt}.utf8.converted"
|
||||
done
|
||||
@ -122,13 +115,11 @@ $ man iconv
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: http://www.tecmint.com/convert-files-to-utf-8-encoding-in-linux/#
|
||||
via: http://www.tecmint.com/convert-files-to-utf-8-encoding-in-linux/
|
||||
|
||||
作者：[Aaron Kili][a]
|
||||
|
||||
译者：[StdioA](https://github.com/StdioA)
|
||||
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
校对：[wxy](https://github.com/wxy)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
@ -0,0 +1,116 @@
|
||||
如何在 Linux 中压缩及解压缩 .bz2 文件
|
||||
============================================================
|
||||
|
||||
对文件进行压缩，可以通过使用较少的字节对文件中的数据进行编码来显著地减小文件的大小，并且在跨网络的[文件的备份和传送][1]时很有用。 另一方面，解压文件意味着将文件中的数据恢复到初始状态。
|
||||
|
||||
Linux 中有几个[文件压缩和解压缩工具][2]，比如gzip、7-zip、Lrzip、[PeaZip][3] 等等。
|
||||
|
||||
本篇教程中，我们将介绍如何在 Linux 中使用 bzip2 工具压缩及解压缩`.bz2`文件。
|
||||
|
||||
bzip2 是一个非常有名的压缩工具，并且在大多数主流 Linux 发行版上都有，你可以在你的发行版上用合适的命令来安装它。
|
||||
|
||||
```
|
||||
$ sudo apt install bzip2 [On Debian/Ubuntu]
|
||||
$ sudo yum install bzip2 [On CentOS/RHEL]
|
||||
$ sudo dnf install bzip2 [On Fedora 22+]
|
||||
```
|
||||
|
||||
使用 bzip2 的常规语法是：
|
||||
|
||||
```
|
||||
$ bzip2 option(s) filenames
|
||||
```
|
||||
|
||||
### 如何在 Linux 中使用“bzip2”压缩文件
|
||||
|
||||
你可以如下压缩一个文件，使用`-z`标志启用压缩：
|
||||
|
||||
```
|
||||
$ bzip2 filename
|
||||
或者
|
||||
$ bzip2 -z filename
|
||||
```
|
||||
|
||||
要压缩一个`.tar`文件，使用的命令为：
|
||||
|
||||
```
|
||||
$ bzip2 -z backup.tar
|
||||
```
|
||||
|
||||
重要：bzip2 默认会在压缩及解压缩文件时删除输入文件（原文件），要保留输入文件，使用`-k`或者`--keep`选项。
|
||||
|
||||
此外，`-f`或者`--force`标志会强制让 bzip2 覆盖已有的输出文件。
|
||||
|
||||
```
|
||||
------ 要保留输入文件 ------
|
||||
$ bzip2 -zk filename
|
||||
$ bzip2 -zk backup.tar
|
||||
```
|
||||
|
||||
你也可以设置块的大小，从 100k 到 900k，分别使用`-1`或者`--fast`到`-9`或者`--best`：
|
||||
|
||||
```
|
||||
$ bzip2 -k1 Etcher-linux-x64.AppImage
|
||||
$ ls -lh Etcher-linux-x64.AppImage.bz2
|
||||
$ bzip2 -k9 Etcher-linux-x64.AppImage
|
||||
$ bzip2 -kf9 Etcher-linux-x64.AppImage
|
||||
$ ls -lh Etcher-linux-x64.AppImage.bz2
|
||||
```
|
||||
|
||||
下面的截屏展示了如何使用选项来保留输入文件，强制 bzip2 覆盖输出文件，并且在压缩中设置块的大小。
|
||||
|
||||
|
||||
|
||||
*在 Linux 中使用 bzip2 压缩文件*
|
||||
|
||||
### 如何在 Linux 中使用“bzip2”解压缩文件
|
||||
|
||||
要解压缩`.bz2`文件，确保使用`-d`或者`--decompress`选项：
|
||||
|
||||
```
|
||||
$ bzip2 -d filename.bz2
|
||||
```
|
||||
|
||||
注意：这个文件必须是`.bz2`的扩展名，上面的命令才能使用。
|
||||
|
||||
```
|
||||
$ bzip2 -vd Etcher-linux-x64.AppImage.bz2
|
||||
$ bzip2 -vfd Etcher-linux-x64.AppImage.bz2
|
||||
$ ls -l Etcher-linux-x64.AppImage
|
||||
```
|
||||
|
||||
|
||||
|
||||
*在 Linux 中解压 bzip2 文件*
|
||||
|
||||
要浏览 bzip2 的帮助及 man 页面，输入下面的命令：
|
||||
|
||||
```
|
||||
$ bzip2 -h
|
||||
$ man bzip2
|
||||
```
|
||||
|
||||
最后，通过上面简单的阐述，我相信你现在已经可以在 Linux 中压缩及解压缩`bz2`文件了。然而，有任何的问题和反馈，可以在评论区中留言。
|
||||
|
||||
重要的是，你可能想在 Linux 中查看一些重要的 [tar 命令示例][6]，以便学习使用 tar 命令来[创建压缩归档文件][7]。
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: http://www.tecmint.com/linux-compress-decompress-bz2-files-using-bzip2
|
||||
|
||||
作者：[Aaron Kili][a]
|
||||
译者：[geekpi](https://github.com/geekpi)
|
||||
校对：[wxy](https://github.com/wxy)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:http://www.tecmint.com/author/aaronkili/
|
||||
[1]:http://www.tecmint.com/rsync-local-remote-file-synchronization-commands/
|
||||
[2]:http://www.tecmint.com/command-line-archive-tools-for-linux/
|
||||
[3]:http://www.tecmint.com/peazip-linux-file-manager-and-file-archive-tool/
|
||||
[4]:http://www.tecmint.com/wp-content/uploads/2016/11/Compress-Files-Using-bzip2-in-Linux.png
|
||||
[5]:http://www.tecmint.com/wp-content/uploads/2016/11/Decompression-bzip2-File-in-Linux.png
|
||||
[6]:http://www.tecmint.com/18-tar-command-examples-in-linux/
|
||||
[7]:http://www.tecmint.com/compress-files-and-finding-files-in-linux/
|
||||
|
||||
|
||||
@ -0,0 +1,241 @@
|
||||
在 Kali Linux 下实战 Nmap（网络安全扫描器）
|
||||
========
|
||||
|
||||
在这第二篇 Kali Linux 文章中, 将讨论称为 ‘[nmap][30]‘ 的网络工具。虽然 nmap 不是 Kali 下唯一的一个工具，但它是最[有用的网络映射工具][29]之一。
|
||||
|
||||
- [第一部分-为初学者准备的Kali Linux安装指南][4]
|
||||
|
||||
Nmap， 是 Network Mapper 的缩写，由 Gordon Lyon 维护(更多关于 Mr. Lyon 的信息在这里: [http://insecure.org/fyodor/][28]) ，并被世界各地许多的安全专业人员使用。
|
||||
|
||||
这个工具在 Linux 和 Windows 下都能使用，并且是用命令行驱动的。相对于那些令人害怕的命令行，对于 nmap，在这里有一个美妙的图形化前端叫做 zenmap。
|
||||
|
||||
强烈建议个人去学习 nmap 的命令行版本，因为与图形化版本 zenmap 相比，它提供了更多的灵活性。
|
||||
|
||||
对服务器进行 nmap 扫描的目的是什么？很好的问题。Nmap 允许管理员快速彻底地了解网络上的系统，因此，它的名字叫 Network MAPper 或者 nmap。
|
||||
|
||||
Nmap 能够快速找到活动的主机和与该主机相关联的服务。Nmap 的功能还可以通过结合 Nmap 脚本引擎（通常缩写为 NSE）进一步被扩展。
|
||||
|
||||
这个脚本引擎允许管理员快速创建可用于确定其网络上是否存在新发现的漏洞的脚本。已经有许多脚本被开发出来并且包含在大多数的 nmap 安装中。
|
||||
|
||||
提醒一句 - 使用 nmap 的人既可能是善意的，也可能是恶意的。应该非常小心，确保你不要使用 nmap 对没有明确得到书面许可的系统进行扫描。请在使用 nmap 工具的时候注意！
|
||||
|
||||
#### 系统要求
|
||||
|
||||
1. [Kali Linux][3] (nmap 可以用于其他操作系统，并且功能也和这个指南里面讲的类似)。
|
||||
2. 另一台计算机，并且装有 nmap 的计算机有权限扫描它 - 这通常很容易通过软件来实现，例如通过 [VirtualBox][2] 创建虚拟机。
|
||||
1. 想要有一个好的机器来练习一下，可以了解一下 Metasploitable 2。
|
||||
2. 下载 MS2 ：[Metasploitable2][1]。
|
||||
3. 一个可以工作的网络连接，或者是使用虚拟机就可以为这两台计算机建立有效的内部网络连接。
|
||||
|
||||
### Kali Linux – 使用 Nmap
|
||||
|
||||
使用 nmap 的第一步是登录 Kali Linux，如果需要，就启动一个图形会话（本系列的第一篇文章安装了 [Kali Linux 的 Enlightenment 桌面环境] [27]）。
|
||||
|
||||
在安装过程中，安装程序将提示用户输入用来登录的“root”用户和密码。 一旦登录到 Kali Linux 机器，使用命令`startx`就可以启动 Enlightenment 桌面环境 - 值得注意的是 nmap 不需要运行桌面环境。
|
||||
|
||||
```
|
||||
# startx
|
||||
|
||||
```
|
||||
|
||||
|
||||
*在 Kali Linux 中启动桌面环境*
|
||||
|
||||
一旦登录到 Enlightenment，将需要打开终端窗口。通过点击桌面背景，将会出现一个菜单。导航到终端可以进行如下操作：应用程序 -> 系统 -> 'Xterm' 或 'UXterm' 或 '根终端'。
|
||||
|
||||
作者是名为 '[Terminator] [25]' 的 shell 程序的粉丝，但是这可能不会显示在 Kali Linux 的默认安装中。这里列出的所有 shell 程序都可用于使用 nmap 。
|
||||
|
||||
|
||||
|
||||
*在 Kali Linux 下启动终端*
|
||||
|
||||
一旦终端启动，nmap 的乐趣就开始了。 对于这个特定的教程，将会创建一个 Kali 机器和 Metasploitable机器之间的私有网络。
|
||||
|
||||
这会使事情变得更容易和更安全，因为私有的网络范围将确保扫描保持在安全的机器上，防止易受攻击的 Metasploitable 机器被其他人攻击。
|
||||
|
||||
### 怎样在我的网络上找到活动主机
|
||||
|
||||
在此示例中，这两台计算机都位于专用的 192.168.56.0/24 网络上。 Kali 机器的 IP 地址为 192.168.56.101，要扫描的 Metasploitable 机器的 IP 地址为 192.168.56.102。
|
||||
|
||||
假如我们不知道 IP 地址信息，但是可以通过快速 nmap 扫描来帮助确定在特定网络上哪些是活动主机。这种扫描称为 “简单列表” 扫描，将 `-sL`参数传递给 nmap 命令。
|
||||
|
||||
```
|
||||
# nmap -sL 192.168.56.0/24
|
||||
|
||||
```
|
||||
|
||||
|
||||
|
||||
*Nmap – 扫描网络上的活动主机*
|
||||
|
||||
悲伤的是，这个初始扫描没有返回任何活动主机。 有时，这是某些操作系统处理[端口扫描网络流量][22]的一个方法。
|
||||
|
||||
###在我的网络中找到并 ping 所有活动主机
|
||||
|
||||
不用担心，在这里有一些技巧可以使 nmap 尝试找到这些机器。 下一个技巧会告诉 nmap 尝试去 ping 192.168.56.0/24 网络中的所有地址。
|
||||
|
||||
```
|
||||
# nmap -sn 192.168.56.0/24
|
||||
|
||||
```
|
||||
|
||||
|
||||
*Nmap – Ping 所有已连接的活动网络主机*
|
||||
|
||||
这次 nmap 会返回一些潜在的主机来进行扫描！ 在此命令中，`-sn` 禁用 nmap 的尝试对主机端口扫描的默认行为，只是让 nmap 尝试 ping 主机。
|
||||
|
||||
### 找到主机上的开放端口
|
||||
|
||||
让我们尝试让 nmap 端口扫描这些特定的主机，看看会出现什么。
|
||||
|
||||
```
|
||||
# nmap 192.168.56.1,100-102
|
||||
|
||||
```
|
||||
|
||||
|
||||
*Nmap – 在主机上扫描网络端口*
|
||||
|
||||
哇! 这一次 nmap 挖到了一个金矿。 这个特定的主机有相当多的[开放网络端口][19]。
|
||||
|
||||
这些端口全都代表着在此特定机器上的某种监听服务。 我们前面说过，192.168.56.102 的 IP 地址会分配给一台易受攻击的机器，这就是为什么在这个主机上会有这么多[开放端口][18]。
|
||||
|
||||
在大多数机器上打开这么多端口是非常不正常的，所以赶快调查这台机器是个明智的想法。管理员可以检查下网络上的物理机器，并在本地查看这些机器，但这不会很有趣，特别是当 nmap 可以为我们更快地做到时！
|
||||
|
||||
### 找到主机上监听端口的服务
|
||||
|
||||
下一个扫描是服务扫描，通常用于尝试确定机器上什么[服务监听在特定的端口][17]。
|
||||
|
||||
Nmap 将探测所有打开的端口，并尝试从每个端口上运行的服务中获取信息。
|
||||
|
||||
```
|
||||
# nmap -sV 192.168.56.102
|
||||
|
||||
```
|
||||
|
||||
|
||||
|
||||
*Nmap – 扫描网络服务监听端口*
|
||||
|
||||
请注意这次 nmap 提供了一些关于 nmap 在特定端口运行的建议（在白框中突出显示），而且 nmap 也试图确认运行在这台机器上的[这个操作系统的信息][15]和它的主机名（也非常成功！）。
|
||||
|
||||
查看这个输出，应该引起网络管理员相当多的关注。 第一行声称 VSftpd 版本 2.3.4 正在这台机器上运行！ 这是一个真正的旧版本的 VSftpd。
|
||||
|
||||
通过查找 ExploitDB，对于这个版本早在 2001 年就发现了一个非常严重的漏洞（ExploitDB ID – 17491）。
|
||||
|
||||
### 发现主机上上匿名 ftp 登录
|
||||
|
||||
让我们使用 nmap 更加清楚的查看这个端口，并且看看可以确认什么。
|
||||
|
||||
```
|
||||
# nmap -sC 192.168.56.102 -p 21
|
||||
|
||||
```
|
||||
|
||||
|
||||
|
||||
*Nmap – 扫描机器上的特定端口*
|
||||
|
||||
使用此命令，让 nmap 在主机上的 FTP 端口（`-p 21`）上运行其默认脚本（`-sC`）。 虽然它可能是、也可能不是一个问题，但是 nmap 确实发现在这个特定的服务器[是允许匿名 FTP 登录的][13]。
|
||||
|
||||
### 检查主机上的漏洞
|
||||
|
||||
这与我们早先知道 VSftd 有旧漏洞的知识相匹配，应该引起一些关注。 让我们看看 nmap有没有脚本来尝试检查 VSftpd 漏洞。
|
||||
|
||||
```
|
||||
# locate .nse | grep ftp
|
||||
|
||||
```
|
||||
|
||||
|
||||
|
||||
*Nmap – 扫描 VSftpd 漏洞*
|
||||
|
||||
注意 nmap 已有一个 NSE 脚本已经用来处理 VSftpd 后门问题！让我们尝试对这个主机运行这个脚本，看看会发生什么，但首先知道如何使用脚本可能是很重要的。
|
||||
|
||||
```
|
||||
# nmap --script-help=ftp-vsftd-backdoor.nse
|
||||
|
||||
```
|
||||
|
||||
|
||||
|
||||
*了解 Nmap NSE 脚本使用*
|
||||
|
||||
通过这个描述，很明显，这个脚本可以用来试图查看这个特定的机器是否容易受到先前识别的 ExploitDB 问题的影响。
|
||||
|
||||
让我们运行这个脚本，看看会发生什么。
|
||||
|
||||
```
|
||||
# nmap --script=ftp-vsftpd-backdoor.nse 192.168.56.102 -p 21
|
||||
|
||||
```
|
||||
|
||||
|
||||
|
||||
*Nmap – 扫描易受攻击的主机*
|
||||
|
||||
耶！Nmap 的脚本返回了一些危险的消息。 这台机器可能面临风险，之后可以进行更加详细的调查。虽然这并不意味着机器缺乏对风险的抵抗力和可以被用于做一些可怕/糟糕的事情，但它应该给网络/安全团队带来一些关注。
|
||||
|
||||
Nmap 具有极高的选择性，非常平稳。 到目前为止已经做的大多数扫描， nmap 的网络流量都保持适度平稳，然而以这种方式扫描对个人拥有的网络可能是非常耗时的。
|
||||
|
||||
Nmap 有能力做一个更积极的扫描，往往一个命令就会产生之前几个命令一样的信息。 让我们来看看积极的扫描的输出（注意 - 积极的扫描会触发[入侵检测/预防系统][9]!）。
|
||||
|
||||
```
|
||||
# nmap -A 192.168.56.102
|
||||
|
||||
```
|
||||
|
||||
|
||||
*Nmap – 在主机上完成网络扫描*
|
||||
|
||||
注意这一次，使用一个命令，nmap 返回了很多关于在这台特定机器上运行的开放端口、服务和配置的信息。 这些信息中的大部分可用于帮助确定[如何保护本机][7]以及评估网络上可能运行的软件。
|
||||
|
||||
这只是 nmap 可用于在主机或网段上找到的许多有用信息的很短的一个列表。强烈敦促个人在个人拥有的网络上继续[以nmap][6] 进行实验。（不要通过扫描其他主机来练习！）。
|
||||
|
||||
有一个关于 Nmap 网络扫描的官方指南，作者 Gordon Lyon，可从[亚马逊](http://amzn.to/2eFNYrD)上获得。
|
||||
|
||||
方便的话可以留下你的评论和问题（或者使用 nmap 扫描器的技巧）。
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: http://www.tecmint.com/nmap-network-security-scanner-in-kali-linux/
|
||||
|
||||
作者：[Rob Turner][a]
|
||||
译者：[DockerChen](https://github.com/DockerChen)
|
||||
校对：[wxy](https://github.com/wxy)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:http://www.tecmint.com/author/robturner/
|
||||
[1]:https://sourceforge.net/projects/metasploitable/files/Metasploitable2/
|
||||
[2]:http://www.tecmint.com/install-virtualbox-on-redhat-centos-fedora/
|
||||
[3]:http://www.tecmint.com/kali-linux-installation-guide
|
||||
[4]:http://www.tecmint.com/kali-linux-installation-guide
|
||||
[5]:http://amzn.to/2eFNYrD
|
||||
[6]:http://www.tecmint.com/nmap-command-examples/
|
||||
[7]:http://www.tecmint.com/security-and-hardening-centos-7-guide/
|
||||
[8]:http://www.tecmint.com/wp-content/uploads/2016/11/Nmap-Scan-Network-Host.png
|
||||
[9]:http://www.tecmint.com/protect-apache-using-mod_security-and-mod_evasive-on-rhel-centos-fedora/
|
||||
[10]:http://www.tecmint.com/wp-content/uploads/2016/11/Nmap-Scan-Host-for-Vulnerable.png
|
||||
[11]:http://www.tecmint.com/wp-content/uploads/2016/11/Nmap-Learn-NSE-Script.png
|
||||
[12]:http://www.tecmint.com/wp-content/uploads/2016/11/Nmap-Scan-Service-Vulnerability.png
|
||||
[13]:http://www.tecmint.com/setup-ftp-anonymous-logins-in-linux/
|
||||
[14]:http://www.tecmint.com/wp-content/uploads/2016/11/Nmap-Scan-Particular-Port-on-Host.png
|
||||
[15]:http://www.tecmint.com/commands-to-collect-system-and-hardware-information-in-linux/
|
||||
[16]:http://www.tecmint.com/wp-content/uploads/2016/11/Nmap-Scan-Network-Services-Ports.png
|
||||
[17]:http://www.tecmint.com/find-linux-processes-memory-ram-cpu-usage/
|
||||
[18]:http://www.tecmint.com/find-open-ports-in-linux/
|
||||
[19]:http://www.tecmint.com/find-open-ports-in-linux/
|
||||
[20]:http://www.tecmint.com/wp-content/uploads/2016/11/Nmap-Scan-for-Ports-on-Hosts.png
|
||||
[21]:http://www.tecmint.com/wp-content/uploads/2016/11/Nmap-Ping-All-Network-Live-Hosts.png
|
||||
[22]:http://www.tecmint.com/audit-network-performance-security-and-troubleshooting-in-linux/
|
||||
[23]:http://www.tecmint.com/wp-content/uploads/2016/11/Nmap-Scan-Network.png
|
||||
[24]:http://www.tecmint.com/wp-content/uploads/2016/11/Launch-Terminal-in-Kali-Linux.png
|
||||
[25]:http://www.tecmint.com/terminator-a-linux-terminal-emulator-to-manage-multiple-terminal-windows/
|
||||
[26]:http://www.tecmint.com/wp-content/uploads/2016/11/Start-Desktop-Environment-in-Kali-Linux.png
|
||||
[27]:http://www.tecmint.com/kali-linux-installation-guide
|
||||
[28]:http://insecure.org/fyodor/
|
||||
[29]:http://www.tecmint.com/bcc-best-linux-performance-monitoring-tools/
|
||||
[30]:http://www.tecmint.com/nmap-command-examples/
|
||||
|
||||
@ -0,0 +1,84 @@
|
||||
通过安装扩展让 KDE Plasma 5 桌面看起来感觉就像 Windows 10 桌面
|
||||
============================================================
|
||||
|
||||
|
||||
|
||||
通过一些步骤，我将告诉你如何把 KDE Plasma 5 桌面变成 Windows 10 桌面。
|
||||
|
||||
|
||||
除了菜单， KDE Plasma 桌面的许多地方已经和 Win 10 桌面非常像了。因此，只需要一点点改动就可以使二者看起来几乎是一样。
|
||||
|
||||
### 开始菜单
|
||||
|
||||
让 KDE Plasma 桌面看起来像 Win 10 桌面的首要以及可能最有标志性的环节是实现 Win 10 的 ‘开始’ 菜单。
|
||||
|
||||
通过安装 [Zren's Tiled Menu][1]，这很容易实现。
|
||||
|
||||
#### 安装
|
||||
|
||||
1、 在 KDE Plasma 桌面上单击右键 -> 解锁窗口部件（Unlock Widgets）
|
||||
|
||||
2、 在 KDE Plasma 桌面上单击右键 -> 增添窗口部件（ Add Widgets）
|
||||
|
||||
3、 获取新窗口部件 -> 下载新的 Plasma 窗口部件（Download New Plasma Widgets）
|
||||
|
||||
4、 搜索“Tiled Menu” -> 安装（Install）
|
||||
|
||||
#### 激活
|
||||
|
||||
1、 在你当前的菜单按钮上单击右键 -> 替代……（Alternatives…）
|
||||
|
||||
2、 选择 "TIled Mune" ->点击切换（Switch）
|
||||
|
||||
|
||||
|
||||
*KDE Tiled 菜单扩展*
|
||||
|
||||
### 主题
|
||||
|
||||
弄好菜单以后，下一个你可能需要的就是主题。幸运的是， [K10ne][3] 提供了一个 WIn 10 主题体验。
|
||||
|
||||
#### 安装：
|
||||
|
||||
1、 从 Plasma 桌面菜单打开“系统设置（System Settings）” -> 工作空间主题（Workspace Theme）
|
||||
|
||||
2、 从侧边栏选择“桌面主题（Desktop Theme）” -> 获取新主题（Get new Theme）
|
||||
|
||||
3、 搜索“K10ne” -> 安装（Install）
|
||||
|
||||
#### 激活
|
||||
|
||||
1、 从 Plasma 桌面菜单选择“系统设置（System Settings）” -> 工作空间主题（Workspace Theme）
|
||||
|
||||
2、 从侧边栏选择“桌面主题（Desktop Theme）” -> "K10ne"
|
||||
|
||||
3、 应用（Apply）
|
||||
|
||||
### 任务栏
|
||||
|
||||
最后，为了有一个更加完整的体验，你可能也想拥有一个更加 Win 10 风格的任务栏，
|
||||
|
||||
这次，你需要的安装包，叫做“Icons-only Task Manager”， 在大多数 Linux 发行版中，通常会默认安装。如果没有安装，需要通过你的系统的合适通道来获取它。
|
||||
|
||||
#### 激活
|
||||
|
||||
1、 在 Plasma 桌面上单击右键 -> 打开窗口部件（Unlock Widgets）
|
||||
|
||||
2、 在 Plasma 桌面上单击右键 -> 增添部件（Add Widgets）
|
||||
|
||||
3、 把“Icons-only Task Manager”拖放到你的桌面面板的合适位置。
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://iwf1.com/make-kde-plasma-5-desktop-look-feel-like-windows-10-using-these-extensions/
|
||||
|
||||
作者：[Liron][a]
|
||||
译者：[ucasFL](https://github.com/ucasFL)
|
||||
校对：[wxy](https://github.com/wxy)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:https://iwf1.com/tag/linux
|
||||
[1]:https://github.com/Zren/plasma-applets/tree/master/tiledmenu
|
||||
[2]:http://iwf1.com/wordpress/wp-content/uploads/2016/11/KDE-Tiled-Menu-extension.jpg
|
||||
[3]:https://store.kde.org/p/1153465/
|
||||
89
published/20161114 How to Check Timezone in Linux.md
Normal file
89
published/20161114 How to Check Timezone in Linux.md
Normal file
@ -0,0 +1,89 @@
|
||||
在 Linux 中查看你的时区
|
||||
============================================================
|
||||
|
||||
在这篇短文中，我们将向你简单介绍几种 Linux 下查看系统时区的简单方法。在 Linux 机器中，尤其是生产服务器上的时间管理技能，是在系统管理中一个极其重要的方面。
|
||||
|
||||
Linux 包含多种可用的时间管理工具，比如 `date` 或 `timedatectlcommands`，你可以用它们来获取当前系统时区，也可以[将系统时间与 NTP 服务器同步][1]，来自动地、更精确地进行时间管理。
|
||||
|
||||
好，我们一起来看几种查看我们的 Linux 系统时区的不同方法。
|
||||
|
||||
### 1、我们从使用传统的 `date` 命令开始
|
||||
|
||||
使用下面的命令，来看一看我们的当前时区：
|
||||
|
||||
```
|
||||
$ date
|
||||
```
|
||||
|
||||
或者，你也可以使用下面的命令。其中 `%Z` 格式可以输出字符形式的时区，而 `%z` 输出数字形式的时区：
|
||||
|
||||
```
|
||||
$ date +”%Z %z”
|
||||
```
|
||||
|
||||
|
||||
*查看 Linux 时区*
|
||||
|
||||
注意：`date` 的手册页中包含很多输出格式，你可以利用它们，来替换你的 `date` 命令的输出内容：
|
||||
|
||||
```
|
||||
$ man date
|
||||
```
|
||||
|
||||
### 2、接下来，你同样可以用 `timedatectl` 命令
|
||||
|
||||
当你不带任何参数运行它时，这条命令可以像下图一样，输出系统时间概览，其中包含当前时区：
|
||||
|
||||
```
|
||||
$ timedatectl
|
||||
```
|
||||
|
||||
然后，你可以在命令中提供一条管道，然后用 [grep 命令][3] 来像下面一样，只过滤出时区信息：
|
||||
|
||||
```
|
||||
$ timedatectl | grep “Time zone”
|
||||
```
|
||||
|
||||
|
||||
|
||||
*查看当前 Linux 时区*
|
||||
|
||||
同样，我们可以学习如何使用 timedatectl 来[设置 Linux 时区][5]。
|
||||
|
||||
###3、进一步，显示文件 /etc/timezone 的内容
|
||||
|
||||
使用 [cat 工具][6]显示文件 `/etc/timezone` 的内容，来查看你的时区：
|
||||
|
||||
```
|
||||
$ cat /etc/timezone
|
||||
```
|
||||
|
||||
|
||||
*在 Linux 中查看时区*
|
||||
|
||||
对于 RHEL/CentOS/Fedora 用户，这里还有一条可以起到同样效果的命令：
|
||||
|
||||
```
|
||||
$ grep ZONE /etc/sysconfig/clock
|
||||
```
|
||||
|
||||
就这些了！别忘了在下面的反馈栏中分享你对于这篇文章中的看法。重要的是：你应该通过这篇 Linux 时区管理指南来学习更多系统时间管理的知识，因为它含有很多易于操作的实例。
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: http://www.tecmint.com/check-linux-timezone
|
||||
|
||||
作者：[Aaron Kili][a]
|
||||
译者：[StdioA](https://github.com/StdioA)
|
||||
校对：[wxy](https://github.com/wxy)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:http://www.tecmint.com/author/aaronkili/
|
||||
[1]:http://www.tecmint.com/install-ntp-server-in-centos/
|
||||
[2]:http://www.tecmint.com/wp-content/uploads/2016/10/Find-Linux-Timezone.png
|
||||
[3]:http://www.tecmint.com/12-practical-examples-of-linux-grep-command/
|
||||
[4]:http://www.tecmint.com/wp-content/uploads/2016/10/Find-Current-Linux-Timezone.png
|
||||
[5]:http://www.tecmint.com/set-time-timezone-and-synchronize-time-using-timedatectl-command/
|
||||
[6]:http://www.tecmint.com/13-basic-cat-command-examples-in-linux/
|
||||
[7]:http://www.tecmint.com/wp-content/uploads/2016/10/Check-Timezone-of-Linux.png
|
||||
85
published/ubuntu vs ubuntu on windows.md
Normal file
85
published/ubuntu vs ubuntu on windows.md
Normal file
@ -0,0 +1,85 @@
|
||||
Ubuntu 14.04/16.04 与 Windows 10 周年版 Ubuntu Bash 性能对比
|
||||
===========================
|
||||
|
||||
今年初，当 Microsoft 和 Canonical 发布 [Windows 10 Bash 和 Ubuntu 用户空间][1]，我尝试做了一些初步性能测试 [Ubuntu on Windows 10 对比 原生 Ubuntu][2]，这次我发布更多的，关于原生纯净的 Ubuntu 和基于 Windows 10 的基准对比。
|
||||
|
||||
|
||||
|
||||
Windows 的 Linux 子系统测试完成了所有测试，并随着 Windows 10周年更新放出。 默认的 Ubuntu 用户空间还是 Ubuntu 14.04，但是已经可以升级到 16.04。所以测试首先在 14.04 测试，完成后将系统升级升级到 16.04 版本并重复所有测试。完成所有基于 Windows 的 Ubuntu 子系统测试后，我在同样的系统上干净地安装了 Ubuntu 14.04.5 和 Ubuntu 16.04 LTS 来做性能对比。
|
||||
|
||||
|
||||
|
||||
配置为 Intel i5 6600K Skylake，16G 内存和 256G 东芝 ssd，测试过程中每个操作系统都采用其原生默认配置和软件包。
|
||||
|
||||
|
||||
|
||||
这次 Ubuntu/Bash on Windows 和原生 Ubuntu 对比测试，采用开源软件 [Phoronix 测试套件](http://www.phoronix-test-suite.com/)，完全自动化并可重复测试。
|
||||
|
||||
|
||||
|
||||
首先是 SQLite 嵌入式数据库基准测试。这方面开箱即用的 Ubuntu/Bash on Windows 性能是相当的慢，但是如果将环境从 14.04 升级到 16.04 LTS，性能会快很多。然而，对于繁重磁盘操作的任务，原生 Ubuntu Linux 几乎比 Windows 的子系统 Linux 快了近 2 倍。
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
编译测试作为额外的繁重磁盘操作测试显示，定制的 Windows 子系统真的成倍的限制了 Ubuntu 性能。
|
||||
|
||||
接下来，是一些使用 Stream 的基本的系统内存速度测试：
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
奇怪的是，这些 Stream 内存的基准测试显示 Ubuntu on Windows 的性能比原生的 Ubuntu 好！这个现象同时发生在基于同样的 Windows 却环境不同的 14.04 和 16.04 LTS 上。
|
||||
|
||||
接下来，是一些繁重 CPU 操作测试。
|
||||
|
||||
|
||||
|
||||
通过 Dolfyn 科学测试，Ubuntu On Windows 和原生 Ubuntu 之间的性能其实是相当接近的。 对于 Ubuntu 16.04，由于较新的 GCC 编译器性能衰减，两个平台上的性能都较慢。
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
透过 Fhourstones 测试和 John The Ripper 测试表明，通过在 Windows 的 Linux 子系统运行的 Ubuntu 的性能可以非常接近裸机 Ubuntu Linux 性能！
|
||||
|
||||
|
||||
|
||||
类似于 Stream 测试，x264 结果是另一个奇怪的情况，其中最好的性能实际上是使用 Linux 子系统的 Ubuntu On Windows！
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
计时编译基准测试非常利于裸机 Ubuntu Linux。这是应该是由于大型程序编译需要大量读写磁盘，在先前测试已经发现了，这是基于 Windows 的 Linux 子系统缓慢的一大领域。
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
许多其他的通用开源基准测试表明，严格的针对 CPU 的测试，Windows 子系统的 Ubuntu 的性能是很接近的，甚至是与原生安装在实际硬件中的 Ubuntu Linux 相等。
|
||||
|
||||
最新的 Windows 的 Linux 子系统，测试结果实际上相当令人印象深刻。让人沮丧的仅仅只是持续缓慢的磁盘/文件系统性能，但是对于受 CPU 限制的工作负载，结果是非常引人注目的。还有很罕见的情况， x264 和 Stream 测试，Ubuntu On Windows 上的性能看起来明显优于运行在实际硬件上 的Ubuntu Linux。
|
||||
|
||||
总的来说，体验是十分愉快的，并且在 Ubuntu/Bash on Windows 也没有遇到任何其他的 bug。如果你有还兴趣了解更多关于 Windows 和 Linux 的基准测试，欢迎留言讨论。
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://www.phoronix.com/scan.php?page=article&item=windows10-anv-wsl&num=1
|
||||
|
||||
作者：[Michael Larabel][a]
|
||||
译者：[VicYu/Vic020](http://vicyu.net)
|
||||
校对：[wxy](https://github.com/wxy)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]: http://www.michaellarabel.com/
|
||||
[1]: http://www.phoronix.com/scan.php?page=news_item&px=Ubuntu-User-Space-On-Win10
|
||||
[2]: http://www.phoronix.com/scan.php?page=article&item=windows-10-lxcore&num=1
|
||||
|
||||
@ -1,57 +0,0 @@
|
||||
willcoderwang translating
|
||||
|
||||
# Would You Consider Riding in a Driverless Car?
|
||||
|
||||
|
||||
|
||||
Technology goes through major movements. The last one we entered into was the wearables phase with the Apple Watch and clones, FitBits, and Google Glass. It seems like the next phase they’ve been working on for quite a while is the driverless car.
|
||||
|
||||
|
||||
These cars, sometimes called autonomous cars, self-driving cars, or robotic cars, would literally drive themselves thanks to technology. They detect their surroundings, such as obstacles and signs, and use GPS to find their way. But would they be safe to drive in? We asked our technology-minded writers, “Would you consider riding in a driverless car?
|
||||
|
||||
### Our Opinion
|
||||
|
||||
**Derrik** reports that he would ride in a driver-less car because “_the technology is there and a lot of smart people have been working on it for a long time._” He admits there are issues with them, but for the most part he believes a lot of the accidents happen when a human does get involved. But if you take humans out of the equation, he thinks riding in a driverless car “_would be incredibly safe_.”
|
||||
|
||||
For **Phil**, these cars give him “the willies,” yet he admits that’s only in the abstract as he’s never ridden in one. He agrees with Derrik that the tech is well developed and knows how it works, but then sees himself as “a_ tough sell being a bit of a luddite at heart._” He admits to even rarely using cruise control. Yet he agrees that a driver relying on it too much would be what would make him feel unsafe.
|
||||
|
||||
|
||||
|
||||
**Robert** agrees that “_the concept is a little freaky,_” but in principle he doesn’t see why cars shouldn’t go in that direction. He notes that planes have gone that route and become much safer, and he believes the accidents we see are mainly “_caused by human error due to over-relying on the technology then not knowing what to do when it fails._”
|
||||
|
||||
He’s a bit of an “anxious passenger” as it is, preferring to have control over the situation, so for him much of it would have to do with where he car is being driven. He’d be okay with it if it was driving in the city at slow speeds but definitely not on “motorways of weaving English country roads with barely enough room for two cars to drive past each other.” He and Phil both see English roads as much different than American ones. He suggests letting others be the guinea pigs and joining in after it’s known to be safe.
|
||||
|
||||
For **Mahesh**, he would definitely ride in a driverless car, as he knows that the companies with these cars “_have robust technology and would never put their customers at risk._” He agrees that it depends on the roads that the cars are being driven on.
|
||||
|
||||
My opinion kind of floats in the middle of all the others. While I’m normally one to jump readily into new technology, putting my life at risk makes it different. I agree that the cars have been in development so long they’re bound to be safe. And frankly there are many drivers on the road that are much more dangerous than driverless cars. But like Robert, I think I’ll let others be the guinea pigs and will welcome the technology once it becomes a bit more commonplace.
|
||||
|
||||
### Your Opinion
|
||||
|
||||
Where do you sit with this issue? Do you trust this emerging technology? Or would you be a nervous nelly in one of these cars? Would you consider driving in a driverless car? Jump into the discussion below in the comments.
|
||||
|
||||
<small style="box-sizing: inherit; font-size: 16px;">Image Credit: [Steve Jurvetson][4] and [Steve Jurvetson at Wikimedia Commons][3]</small>
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://www.maketecheasier.com/riding-driverless-car/?utm_medium=feed&utm_source=feedpress.me&utm_campaign=Feed%3A+maketecheasier
|
||||
|
||||
作者：[Laura Tucker][a]
|
||||
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]: https://www.maketecheasier.com/author/lauratucker/
|
||||
[1]:https://www.maketecheasier.com/riding-driverless-car/#comments
|
||||
[2]:https://www.maketecheasier.com/author/lauratucker/
|
||||
[3]:https://commons.m.wikimedia.org/wiki/File:Inside_the_Google_RoboCar_today_with_PlanetLabs.jpg
|
||||
[4]:https://commons.m.wikimedia.org/wiki/File:Jurvetson_Google_driverless_car_trimmed.jpg
|
||||
[5]:https://support.google.com/adsense/troubleshooter/1631343
|
||||
[6]:https://www.maketecheasier.com/best-wordpress-video-plugins/
|
||||
[7]:https://www.maketecheasier.com/hidden-google-games/
|
||||
[8]:mailto:?subject=Would%20You%20Consider%20Riding%20in%20a%20Driverless%20Car?&body=https%3A%2F%2Fwww.maketecheasier.com%2Friding-driverless-car%2F
|
||||
[9]:http://twitter.com/share?url=https%3A%2F%2Fwww.maketecheasier.com%2Friding-driverless-car%2F&text=Would+You+Consider+Riding+in+a+Driverless+Car%3F
|
||||
[10]:http://www.facebook.com/sharer.php?u=https%3A%2F%2Fwww.maketecheasier.com%2Friding-driverless-car%2F
|
||||
[11]:https://www.maketecheasier.com/category/opinion/
|
||||
@ -1,58 +0,0 @@
|
||||
Rusking Translating...
|
||||
|
||||
# Arch Linux: In a world of polish, DIY never felt so good
|
||||
|
||||
|
||||
|
||||
Dig through the annals of Linux journalism and you'll find a surprising amount of coverage of some pretty obscure distros. Flashy new distros like Elementary OS and Solus garner attention for their slick interfaces, and anything shipping with a MATE desktop gets coverage by simple virtue of using MATE.
|
||||
|
||||
Thanks to television shows like _Mr Robot_, I fully expect coverage of even Kali Linux to be on the uptick soon.
|
||||
|
||||
In all that coverage, though, there's one very widely used distro that's almost totally ignored: Arch Linux.
|
||||
|
||||
Arch gets very little coverage for a several reasons, not the least of which is that it's somewhat difficult to install and requires you feel comfortable with the command line to get it working. Worse, from the point of view of anyone trying to appeal to mainstream users, that difficulty is by design - nothing keeps the noobs out like a daunting install process.
|
||||
|
||||
It's a shame, though, because once the installation is complete, Arch is actually - in my experience - far easier to use than any other Linux distro I've tried.
|
||||
|
||||
But yes, installation is a pain. Hand-partitioning, hand-mounting and generating your own `fstab` files takes more time and effort than clicking "install" and merrily heading off to do something else. But the process of installing Arch teaches you a lot. It pulls back the curtain so you can see what's behind it. In fact it makes the curtain disappear entirely. In Arch, _you_ are the person behind the curtain.
|
||||
|
||||
In addition to its reputation for being difficult to install, Arch is justly revered for its customizability, though this is somewhat misunderstood. There is no "default" desktop in Arch. What you want installed on top of the base set of Arch packages is entirely up to you.
|
||||
|
||||
![ARCH "DESKTOP" SCREENSHOT LINUX - OBVS VARIES DEPENDING ON USER ](https://regmedia.co.uk/2016/11/01/arch.jpg?x=648&y=364&infer_y=1 "ARCH "DESKTOP" SCREENSHOT LINUX - OBVS VARIES DEPENDING ON USER ")
|
||||
|
||||
While you can see this as infinite customizability, you can also see it as totally lacking in customization. For example, unlike - say - Ubuntu there is almost no patching or customization happening in Arch. Arch developers simply pass on what upstream developers have released, end of story. For some this good; you can run "pure" GNOME, for instance. But in other cases, some custom patching can take care of bugs that upstream devs might not prioritize.
|
||||
|
||||
The lack of a default set of applications and desktop system also does not make for tidy reviews - or reviews at all really, since what I install will no doubt be different to what you choose. I happened to select a very minimal setup of bare Openbox, tint2 and dmenu. You might prefer the latest release of GNOME. We'd both be running Arch, but our experiences of it would be totally different. This is of course true of any distro, but most others have a default desktop at least.
|
||||
|
||||
Still there are common elements that together can make the basis of an Arch review. There is, for example, the primary reason I switched - Arch is a rolling release distro. This means two things. First, the latest kernels are delivered as soon as they're available and reasonably stable. This means I can test things that are difficult to test with other distros. The other big win for a rolling distro is that all updates are delivered when they're ready. Not only does this mean newer software sooner, it means there's no massive system updates that might break things.
|
||||
|
||||
Many people feel that Arch is less stable because it's rolling, but in my experience over the last nine months I would argue the opposite.
|
||||
|
||||
I have yet to break anything with an update. I did once have to rollback because my /boot partition wasn't mounted when I updated and changes weren't written, but that was pure user error. Bugs that do surface (like some regressions related to the trackpad on a Dell XPS laptop I was testing) are fixed and updates are available much faster than they would be with a non-rolling distro. In short, I've found Arch's rolling release updates to be far more stable than anything else I've been using along side it. The only caveat I have to add to that is read the wiki and pay close attention to what you're updating.
|
||||
|
||||
This brings us to the main reason I suspect that Arch's appeal is limited - you have to pay attention to what you're doing. Blindly updating Arch is risky - but it's risky with any distro; you've just been conditioned to think it's not because you have no choice.
|
||||
|
||||
All of which leads me to the other major reason I embraced Arch - the [Arch Philosophy][1]. The part in particular that I find appealing is this bit: "[Arch] is targeted at the proficient GNU/Linux user, or anyone with a do-it-yourself attitude who is willing to read the documentation, and solve their own problems."
|
||||
|
||||
As Linux moves further into the mainstream developers seem to feel a greater need to smooth over all the rough areas - as if mirroring the opaque user experience of proprietary software were somehow the apex of functionality.
|
||||
|
||||
Strange though it sounds in this day and age, there are many of us who actually prefer to configure things ourselves. In this sense Arch may well be the last refuge of the DIY Linux user. ®
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: http://www.theregister.co.uk/2016/11/02/arch_linux_taster/
|
||||
|
||||
作者：[Scott Gilbertson][a]
|
||||
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:http://www.theregister.co.uk/Author/1785
|
||||
[1]:https://wiki.archlinux.org/index.php/Arch_Linux
|
||||
[2]:http://www.theregister.co.uk/Author/1785
|
||||
[3]:https://www.linkedin.com/shareArticle?mini=true&url=http://www.theregister.co.uk/2016/11/02/arch_linux_taster/&title=Arch%20Linux%3A%20In%20a%20world%20of%20polish%2C%20DIY%20never%20felt%20so%20good&summary=Last%20refuge%20for%20purists
|
||||
[4]:http://twitter.com/share?text=Arch%20Linux%3A%20In%20a%20world%20of%20polish%2C%20DIY%20never%20felt%20so%20good&url=http://www.theregister.co.uk/2016/11/02/arch_linux_taster/&via=theregister
|
||||
[5]:http://www.reddit.com/submit?url=http://www.theregister.co.uk/2016/11/02/arch_linux_taster/&title=Arch%20Linux%3A%20In%20a%20world%20of%20polish%2C%20DIY%20never%20felt%20so%20good
|
||||
@ -0,0 +1,86 @@
|
||||
willcoderewang 翻译中
|
||||
|
||||
How To Manually Backup Your SMS / MMS Messages On Android?
|
||||
============================================================
|
||||
|
||||
|
||||
|
||||
If you’re switching a device or upgrading your system, making a backup of your data might be of crucial importance.
|
||||
|
||||
|
||||
One of the places where our important data may lie, is in our SMS / MMS messages, be it of sentimental or utilizable value, backing it up might prove quite useful.
|
||||
|
||||
However, unlike our photos, videos or song files which can be transferred and backed up with relative ease, backing our SMS / MMS usually proves to be a bit more complicated task that commonly require involving a third party-app or service.
|
||||
|
||||
### Why Do It Manually?
|
||||
|
||||
Although there currently exist quite a bit of different apps that might take care of backing SMS and MMS for you, you may want to consider doing it manually for the following reasons:
|
||||
|
||||
1. Apps **may not work** on different devices or different Android versions.
|
||||
2. Apps may backup your data by uploading it to the Internet cloud therefore requiring you to **jeopardize the safety** of your content.
|
||||
3. By backing up manually, you have complete control over where your data goes and what it goes through, thus **limiting the risk of spyware** in the process.
|
||||
4. Doing it manually can be overall **less time consuming, easier and more straightforward**than any other way.
|
||||
|
||||
### How To Backup SMS / MMS Manually?
|
||||
|
||||
To backup your SMS / MMS messages manually you’ll need to have an Android tool called [adb][1]installed on your computer.
|
||||
|
||||
Now, the important thing to know regarding SMS / MMS is that Android stores them in a database commonly named **mmssms.db.**
|
||||
|
||||
Since the location of that database may differ between one device to another and also because other SMS apps can create databases of their own, such as, gommssms.db created by GO SMS app, the first thing you’d want to do is to search for these databases.
|
||||
|
||||
So, open up your CLI tool (I use Linux Terminal, you may use Windows CMD or PowerShell) and issue the following commands:
|
||||
|
||||
Note: below is a series of commands needed for the task and later is the explanation of what each command does.
|
||||
|
||||
`
|
||||
adb root
|
||||
|
||||
adb shell
|
||||
|
||||
find / -name "*mmssms*"
|
||||
|
||||
exit
|
||||
|
||||
adb pull /PATH/TO/mmssms.db /PATH/TO/DESTINATION/FOLDER
|
||||
|
||||
`
|
||||
|
||||
#### Explanation:
|
||||
|
||||
We start with adb root command in order to start adb in root mode – so that we’ll have permissions to reach system protected files as well.
|
||||
|
||||
“adb shell” is used to get inside the device shell.
|
||||
|
||||
Next, the “find” command is used to search for the databases. (in my case it’s found in: /data/data/com.android.providers.telephony/databases/mmssms.db)
|
||||
|
||||
* Tip: if your Terminal prints too many irrelevant results, try refining your “find” parameters (google it).
|
||||
|
||||
[
|
||||
|
||||
][2]
|
||||
|
||||
Android SMS&MMS databases
|
||||
|
||||
Then we use exit command in order to exit back to our local system directory.
|
||||
|
||||
Lastly, adb pull is used to copy the database files into a folder on our computer.
|
||||
|
||||
Now, once you’re ready to restore your SMS / MMS messages, whether it’s on a new device or a new system version, simply search again for the location of mmssms on the new system and replace it with the one you’ve backed.
|
||||
|
||||
Use adb push to replace it, e.g: adb push ~/Downloads/mmssms.db /data/data/com.android.providers.telephony/databases/mmssms.db
|
||||
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://iwf1.com/how-to-manually-backup-your-sms-mms-messages-on-android/
|
||||
|
||||
作者：[Liron ][a]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:https://iwf1.com/tag/android
|
||||
[1]:http://developer.android.com/tools/help/adb.html
|
||||
[2]:http://iwf1.com/wordpress/wp-content/uploads/2016/10/Android-SMSMMS-databases.jpg
|
||||
@ -0,0 +1,100 @@
|
||||
Livepatch – Apply Critical Security Patches to Ubuntu Linux Kernel Without Rebooting
|
||||
============================================================
|
||||
|
||||
If you are a system administrator in charge of maintaining critical systems in enterprise environments, we are sure you know two important things:
|
||||
|
||||
1) Finding a downtime window to install security patches in order to handle kernel or operating system vulnerabilities can be difficult. If the company or business you work for does not have security policies in place, operations management may end up favoring uptime over the need to solve vulnerabilities. Additionally, internal bureaucracy can cause delays in granting approvals for a downtime. Been there myself.
|
||||
|
||||
2) Sometimes you can’t really afford a downtime, and should be prepared to mitigate any potential exposures to malicious attacks some other way.
|
||||
|
||||
The good news is that Canonical has recently released (actually, a couple of days ago) its Livepatchservice to apply critical kernel patches to Ubuntu 16.04 (64-bit edition / 4.4.x kernel) without the need for a later reboot. Yes, you read that right: with Livepatch, you don’t need to restart your Ubuntu 16.04 server in order for the security patches to take effect.
|
||||
|
||||
### Signing up for Ubuntu Livepatch
|
||||
|
||||
In order to use Canonical Livepatch Service, you need to sign up at [https://auth.livepatch.canonical.com/][1] and indicate if you are a regular Ubuntu user or an Advantage subscriber (paid option). All Ubuntu users can link up to 3 different machines to Livepatch through the use of a token:
|
||||
|
||||
[
|
||||
|
||||
][2]
|
||||
|
||||
Canonical Livepatch Service
|
||||
|
||||
In the next step you will be prompted to enter your Ubuntu One credentials or sign up for a new account. If you choose the latter, you will need to confirm your email address in order to finish your registration:
|
||||
|
||||
[
|
||||
|
||||
][3]
|
||||
|
||||
Ubuntu One Confirmation Mail
|
||||
|
||||
Once you click on the link above to confirm your email address, you’ll be ready to go back to [https://auth.livepatch.canonical.com/][4] and get your Livepatch token.
|
||||
|
||||
### Getting and Using your Livepatch Token
|
||||
|
||||
To begin, copy the unique token assigned to your Ubuntu One account:
|
||||
|
||||
[
|
||||
|
||||
][5]
|
||||
|
||||
Canonical Livepatch Token
|
||||
|
||||
Then go to a terminal and type:
|
||||
|
||||
```
|
||||
$ sudo snap install canonical-livepatch
|
||||
```
|
||||
|
||||
The above command will install the livepatch, whereas
|
||||
|
||||
```
|
||||
$ sudo canonical-livepatch enable [YOUR TOKEN HERE]
|
||||
```
|
||||
|
||||
will enable it for your system. If this last command indicates it can’t find canonical-livepatch, make sure `/snap/bin` has been added to your path. A workaround consists of changing your working directory to `/snap/bin` and do.
|
||||
|
||||
```
|
||||
$ sudo ./canonical-livepatch enable [YOUR TOKEN HERE]
|
||||
```
|
||||
[
|
||||
|
||||
][6]
|
||||
|
||||
Install Livepatch in Ubuntu
|
||||
|
||||
Overtime, you’ll want to check the description and the status of patches applied to your kernel. Fortunately, this is as easy as doing.
|
||||
|
||||
```
|
||||
$ sudo ./canonical-livepatch status --verbose
|
||||
```
|
||||
|
||||
as you can see in the following image:
|
||||
|
||||
[
|
||||
|
||||
][7]
|
||||
|
||||
Check Livepatch Status in Ubuntu
|
||||
|
||||
Having enabled Livepatch on your Ubuntu server, you will be able to reduce planned and unplanned downtimes at a minimum while keeping your system secure. Hopefully Canonical’s initiative will award you a pat on the back by management – or better yet, a raise.
|
||||
|
||||
Feel free to let us know if you have any questions about this article. Just drop us a note using the comment form below and we will get back to you as soon as possible.
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: http://www.tecmint.com/livepatch-install-critical-security-patches-to-ubuntu-kernel
|
||||
|
||||
作者：[Gabriel Cánepa][a]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:http://www.tecmint.com/author/gacanepa/
|
||||
[1]:https://auth.livepatch.canonical.com/
|
||||
[2]:http://www.tecmint.com/wp-content/uploads/2016/10/Canonical-Livepatch-Service.png
|
||||
[3]:http://www.tecmint.com/wp-content/uploads/2016/10/Ubuntu-One-Confirmation-Mail.png
|
||||
[4]:https://auth.livepatch.canonical.com/
|
||||
[5]:http://www.tecmint.com/wp-content/uploads/2016/10/Livepatch-Token.png
|
||||
[6]:http://www.tecmint.com/wp-content/uploads/2016/10/Install-Livepatch-in-Ubuntu.png
|
||||
[7]:http://www.tecmint.com/wp-content/uploads/2016/10/Check-Livepatch-Status.png
|
||||
@ -1,3 +1,5 @@
|
||||
FSSlc translating
|
||||
|
||||
HOW TO SHARE STEAM GAME FILES BETWEEN LINUX AND WINDOWS
|
||||
============
|
||||
|
||||
|
||||
@ -1,453 +0,0 @@
|
||||
DTrace for Linux 2016
|
||||
===========
|
||||
|
||||
|
||||
|
||||
With the final major capability for BPF tracing (timed sampling) merging in Linux 4.9-rc1, the Linux kernel now has raw capabilities similar to those provided by DTrace, the advanced tracer from Solaris. As a long time DTrace user and expert, this is an exciting milestone! On Linux, you can now analyze the performance of applications and the kernel using production-safe low-overhead custom tracing, with latency histograms, frequency counts, and more.
|
||||
|
||||
There have been many tracing projects for Linux, but the technology that finally merged didn’t start out as a tracing project at all: it began as enhancements to Berkeley Packet Filter (BPF). At first, these enhancements allowed BPF to redirect packets to create software-defined networks. Later on, support for tracing events was added, enabling programmatic tracing in Linux.
|
||||
|
||||
While BPF currently lacks a high-level language like DTrace, the front-ends available have been enough for me to create many BPF tools, some based on my older [DTraceToolkit][37]. In this post I'll describe how you can use these tools, the front-ends available, and discuss where the technology is going next.
|
||||
|
||||
### Screenshots
|
||||
|
||||
I've been adding BPF-based tracing tools to the open source [bcc][36] project (thanks to Brenden Blanco, of PLUMgrid, for leading bcc development). See the [bcc install][35] instructions. It will add a collection of tools under /usr/share/bcc/tools, including the following.
|
||||
|
||||
Tracing new processes:
|
||||
|
||||
```
|
||||
# **execsnoop**
|
||||
PCOMM PID RET ARGS
|
||||
bash 15887 0 /usr/bin/man ls
|
||||
preconv 15894 0 /usr/bin/preconv -e UTF-8
|
||||
man 15896 0 /usr/bin/tbl
|
||||
man 15897 0 /usr/bin/nroff -mandoc -rLL=169n -rLT=169n -Tutf8
|
||||
man 15898 0 /usr/bin/pager -s
|
||||
nroff 15900 0 /usr/bin/locale charmap
|
||||
nroff 15901 0 /usr/bin/groff -mtty-char -Tutf8 -mandoc -rLL=169n -rLT=169n
|
||||
groff 15902 0 /usr/bin/troff -mtty-char -mandoc -rLL=169n -rLT=169n -Tutf8
|
||||
groff 15903 0 /usr/bin/grotty
|
||||
|
||||
```
|
||||
|
||||
Histogram of disk I/O latency:
|
||||
|
||||
```
|
||||
# **biolatency -m**
|
||||
Tracing block device I/O... Hit Ctrl-C to end.
|
||||
^C
|
||||
msecs : count distribution
|
||||
0 -> 1 : 96 |************************************ |
|
||||
2 -> 3 : 25 |********* |
|
||||
4 -> 7 : 29 |*********** |
|
||||
8 -> 15 : 62 |*********************** |
|
||||
16 -> 31 : 100 |**************************************|
|
||||
32 -> 63 : 62 |*********************** |
|
||||
64 -> 127 : 18 |****** |
|
||||
|
||||
```
|
||||
|
||||
Tracing common ext4 operations slower than 5 milliseconds:
|
||||
|
||||
```
|
||||
# **ext4slower 5**
|
||||
Tracing ext4 operations slower than 5 ms
|
||||
TIME COMM PID T BYTES OFF_KB LAT(ms) FILENAME
|
||||
21:49:45 supervise 3570 W 18 0 5.48 status.new
|
||||
21:49:48 supervise 12770 R 128 0 7.55 run
|
||||
21:49:48 run 12770 R 497 0 16.46 nsswitch.conf
|
||||
21:49:48 run 12770 R 1680 0 17.42 netflix_environment.sh
|
||||
21:49:48 run 12770 R 1079 0 9.53 service_functions.sh
|
||||
21:49:48 run 12772 R 128 0 17.74 svstat
|
||||
21:49:48 svstat 12772 R 18 0 8.67 status
|
||||
21:49:48 run 12774 R 128 0 15.76 stat
|
||||
21:49:48 run 12777 R 128 0 7.89 grep
|
||||
21:49:48 run 12776 R 128 0 8.25 ps
|
||||
21:49:48 run 12780 R 128 0 11.07 xargs
|
||||
21:49:48 ps 12776 R 832 0 12.02 libprocps.so.4.0.0
|
||||
21:49:48 run 12779 R 128 0 13.21 cut
|
||||
[...]
|
||||
|
||||
```
|
||||
|
||||
Tracing new active TCP connections (connect()):
|
||||
|
||||
```
|
||||
# **tcpconnect**
|
||||
PID COMM IP SADDR DADDR DPORT
|
||||
1479 telnet 4 127.0.0.1 127.0.0.1 23
|
||||
1469 curl 4 10.201.219.236 54.245.105.25 80
|
||||
1469 curl 4 10.201.219.236 54.67.101.145 80
|
||||
1991 telnet 6 ::1 ::1 23
|
||||
2015 ssh 6 fe80::2000:bff:fe82:3ac fe80::2000:bff:fe82:3ac 22
|
||||
|
||||
```
|
||||
|
||||
Tracing DNS latency by tracing getaddrinfo()/gethostbyname() library calls:
|
||||
|
||||
```
|
||||
# **gethostlatency**
|
||||
TIME PID COMM LATms HOST
|
||||
06:10:24 28011 wget 90.00 www.iovisor.org
|
||||
06:10:28 28127 wget 0.00 www.iovisor.org
|
||||
06:10:41 28404 wget 9.00 www.netflix.com
|
||||
06:10:48 28544 curl 35.00 www.netflix.com.au
|
||||
06:11:10 29054 curl 31.00 www.plumgrid.com
|
||||
06:11:16 29195 curl 3.00 www.facebook.com
|
||||
06:11:25 29404 curl 72.00 foo
|
||||
06:11:28 29475 curl 1.00 foo
|
||||
|
||||
```
|
||||
|
||||
Interval summaries of VFS operations by type:
|
||||
|
||||
```
|
||||
# **vfsstat**
|
||||
TIME READ/s WRITE/s CREATE/s OPEN/s FSYNC/s
|
||||
18:35:32: 231 12 4 98 0
|
||||
18:35:33: 274 13 4 106 0
|
||||
18:35:34: 586 86 4 251 0
|
||||
18:35:35: 241 15 4 99 0
|
||||
|
||||
```
|
||||
|
||||
Tracing off-CPU time with kernel and user stack traces (summarized in kernel), for a given PID:
|
||||
|
||||
```
|
||||
# **offcputime -d -p 24347**
|
||||
Tracing off-CPU time (us) of PID 24347 by user + kernel stack... Hit Ctrl-C to end.
|
||||
^C
|
||||
[...]
|
||||
ffffffff810a9581 finish_task_switch
|
||||
ffffffff8185d385 schedule
|
||||
ffffffff81085672 do_wait
|
||||
ffffffff8108687b sys_wait4
|
||||
ffffffff81861bf6 entry_SYSCALL_64_fastpath
|
||||
--
|
||||
00007f6733a6b64a waitpid
|
||||
- bash (24347)
|
||||
4952
|
||||
|
||||
ffffffff810a9581 finish_task_switch
|
||||
ffffffff8185d385 schedule
|
||||
ffffffff81860c48 schedule_timeout
|
||||
ffffffff810c5672 wait_woken
|
||||
ffffffff8150715a n_tty_read
|
||||
ffffffff815010f2 tty_read
|
||||
ffffffff8122cd67 __vfs_read
|
||||
ffffffff8122df65 vfs_read
|
||||
ffffffff8122f465 sys_read
|
||||
ffffffff81861bf6 entry_SYSCALL_64_fastpath
|
||||
--
|
||||
00007f6733a969b0 read
|
||||
- bash (24347)
|
||||
1450908
|
||||
|
||||
```
|
||||
|
||||
Tracing MySQL query latency (via a USDT probe):
|
||||
|
||||
```
|
||||
# **mysqld_qslower `pgrep -n mysqld`**
|
||||
Tracing MySQL server queries for PID 14371 slower than 1 ms...
|
||||
TIME(s) PID MS QUERY
|
||||
0.000000 18608 130.751 SELECT * FROM words WHERE word REGEXP '^bre.*n$'
|
||||
2.921535 18608 130.590 SELECT * FROM words WHERE word REGEXP '^alex.*$'
|
||||
4.603549 18608 24.164 SELECT COUNT(*) FROM words
|
||||
9.733847 18608 130.936 SELECT count(*) AS count FROM words WHERE word REGEXP '^bre.*n$'
|
||||
17.864776 18608 130.298 SELECT * FROM words WHERE word REGEXP '^bre.*n$' ORDER BY word
|
||||
|
||||
```
|
||||
|
||||
Using the trace multi-tool to watch login requests, by instrumenting the pam library:
|
||||
|
||||
```
|
||||
# **trace 'pam:pam_start "%s: %s", arg1, arg2'**
|
||||
TIME PID COMM FUNC -
|
||||
17:49:45 5558 sshd pam_start sshd: root
|
||||
17:49:47 5662 sudo pam_start sudo: root
|
||||
17:49:49 5727 login pam_start login: bgregg
|
||||
|
||||
```
|
||||
|
||||
Many tools have usage messages (-h), and all should have man pages and text files of example output in the bcc project.
|
||||
|
||||
### Out of necessity
|
||||
|
||||
In 2014, Linux tracing had some kernel summary features (from ftrace and perf_events), but outside those we still had to dump-and-post-process data – a decades old technique that has high overhead at scale. You couldn't frequency count process names, function names, stack traces, or other arbitrary data in the kernel. You couldn't save variables in one probe event, and then retrieve them in another, which meant that you couldn't measure latency (or time deltas) in custom places, and you couldn't create in-kernel latency histograms. You couldn't trace USDT probes. You couldn't even write custom programs. DTrace could do all these, but only on Solaris or BSD. On Linux, some out-of-tree tracers like SystemTap could serve these needs, but brought their own challenges. (For the sake of completeness: yes, you _could_ write kprobe-based kernel modules – but practically no one did.)
|
||||
|
||||
In 2014 I joined the Netflix cloud performance team. Having spent years as a DTrace expert, it might have seemed crazy for me to move to Linux. But I had some motivations, in particular seeking a greater challenge: performance tuning the Netflix cloud, with its rapid application changes, microservice architecture, and distributed systems. Sometimes this job involves systems tracing, for which I'd previously used DTrace. Without DTrace on Linux, I began by using what was built in to the Linux kernel, ftrace and perf_events, and from them made a toolkit of tracing tools ([perf-tools][34]). They have been invaluable. But I couldn't do some tasks, particularly latency histograms and stack trace counting. We needed kernel tracing to be programmatic.
|
||||
|
||||
### What happened?
|
||||
|
||||
BPF adds programmatic capabilities to the existing kernel tracing facilities (tracepoints, kprobes, uprobes). It has been enhanced rapidly in the Linux 4.x series.
|
||||
|
||||
Timed sampling was the final major piece, and it landed in Linux 4.9-rc1 ([patchset][33]). Many thanks to Alexei Starovoitov (now working on BPF at Facebook), the lead developer behind these BPF enhancements.
|
||||
|
||||
The Linux kernel now has the following features built in (added between 2.6 and 4.9):
|
||||
|
||||
* Dynamic tracing, kernel-level (BPF support for kprobes)
|
||||
* Dynamic tracing, user-level (BPF support for uprobes)
|
||||
* Static tracing, kernel-level (BPF support for tracepoints)
|
||||
* Timed sampling events (BPF with perf_event_open)
|
||||
* PMC events (BPF with perf_event_open)
|
||||
* Filtering (via BPF programs)
|
||||
* Debug output (bpf_trace_printk())
|
||||
* Per-event output (bpf_perf_event_output())
|
||||
* Basic variables (global & per-thread variables, via BPF maps)
|
||||
* Associative arrays (via BPF maps)
|
||||
* Frequency counting (via BPF maps)
|
||||
* Histograms (power-of-2, linear, and custom, via BPF maps)
|
||||
* Timestamps and time deltas (bpf_ktime_get_ns(), and BPF programs)
|
||||
* Stack traces, kernel (BPF stackmap)
|
||||
* Stack traces, user (BPF stackmap)
|
||||
* Overwrite ring buffers (perf_event_attr.write_backward)
|
||||
|
||||
The front-end we are using is bcc, which provides both Python and lua interfaces. bcc adds:
|
||||
|
||||
* Static tracing, user-level (USDT probes via uprobes)
|
||||
* Debug output (Python with BPF.trace_pipe() and BPF.trace_fields())
|
||||
* Per-event output (BPF_PERF_OUTPUT macro and BPF.open_perf_buffer())
|
||||
* Interval output (BPF.get_table() and table.clear())
|
||||
* Histogram printing (table.print_log2_hist())
|
||||
* C struct navigation, kernel-level (bcc rewriter maps to bpf_probe_read())
|
||||
* Symbol resolution, kernel-level (ksym(), ksymaddr())
|
||||
* Symbol resolution, user-level (usymaddr())
|
||||
* BPF tracepoint support (via TRACEPOINT_PROBE)
|
||||
* BPF stack trace support (incl. walk method for stack frames)
|
||||
* Various other helper macros and functions
|
||||
* Examples (under /examples)
|
||||
* Many tools (under /tools)
|
||||
* Tutorials (/docs/tutorial*.md)
|
||||
* Reference guide (/docs/reference_guide.md)
|
||||
|
||||
I'd been holding off on this post until the last major feature was integrated, and now it has been in 4.9-rc1\. There are still some minor missing things we have workarounds for, and additional things we might do, but what we have right now is worth celebrating. Linux now has advanced tracing capabilities built in.
|
||||
|
||||
### Safety
|
||||
|
||||
BPF and its enhancements are designed to be production safe, and it is used today in large scale production environments. But if you're determined, you may be able to still find a way to hang the kernel. That experience should be the exception rather than the rule, and such bugs will be fixed fast, especially since BPF is part of Linux. All eyes are on Linux.
|
||||
|
||||
We did hit a couple of non-BPF bugs during development that needed to be fixed: rcu not reentrant, which could cause kernel hangs for funccount and was fixed by the "bpf: map pre-alloc" patchset in 4.6, and with a workaround in bcc for older kernels. And a uprobe memory accounting issue, which failed uprobe allocations, and was fixed by the "uprobes: Fix the memcg accounting" patch in 4.8 and backported to earlier kernels (eg, it's in the current 4.4.27 and 4.4.0-45.66).
|
||||
|
||||
### Why did Linux tracing take so long?
|
||||
|
||||
Prior work had been split among several other tracers: there was never a consolidated effort on any single one. For more about this and other issues, see my 2014 [tracing summit talk][32]. One thing I didn't note there was the counter effect of partial solutions: some companies had found another tracer (SystemTap or LTTng) was sufficient for their specific needs, and while they have been happy to hear about BPF, contributing to its development wasn't a priority given their existing solution.
|
||||
|
||||
BPF has only been enhanced to do tracing in the last two years. This process could have gone faster, but early on there were zero full-time engineers working on BPF tracing. Alexei Starovoitov (BPF lead), Brenden Blanco (bcc lead), myself, and others, all had other priorities. I tracked my hours on this at Netflix (voluntarily), and I've spent around 7% of my time on BPF/bcc. It wasn't that much of a priority, in part because we had our own workarounds (including my perf-tools, which work on older kernels).
|
||||
|
||||
Now that BPF tracing has arrived, there's already tech companies on the lookout for BPF skills. I can still highly recommend [Netflix][31]. (If you're trying to hire _me_ for BPF skills, then I'm still very happy at Netflix!.)
|
||||
|
||||
### Ease of use
|
||||
|
||||
What might appear to be the largest remaining difference between DTrace and bcc/BPF is ease of use. But it depends on what you're doing with BPF tracing. Either you are:
|
||||
|
||||
* **Using BPF tools/metrics**: There should be no difference. Tools behave the same, GUIs can access similar metrics. Most people will use BPF in this way.
|
||||
* **Developing tools/metrics**: bcc right now is much harder. DTrace has its own concise language, D, similar to awk, whereas bcc uses existing languages (C and Python or lua) with libraries. A bcc tool in C+Python may be a _lot_ more code than a D-only tool: 10x the lines, or more. However, many DTrace tools used shell wrapping to provide arguments and error checking, inflating the code to a much bigger size. The coding difficulty is also different: the rewriter in bcc can get fiddly, which makes some scripts much more complicated to develop (extra bpf_probe_read()s, requiring more knowledge of BPF internals). This situation should improve over time as improvements are planned.
|
||||
* **Running common one-liners**: Fairly similar. DTrace could do many with the "dtrace" command, whereas bcc has a variety of multitools: trace, argdist, funccount, funclatency, etc.
|
||||
* **Writing custom ad hoc one-liners**: With DTrace this was trivial, and accelerated advanced analysis by allowing rapid custom questions to be posed and answered by the system. bcc is currently limited by its multitools and their scope.
|
||||
|
||||
In short, if you're an end user of BPF tools, you shouldn't notice these differences. If you're an advanced user and tool developer (like me), bcc is a lot more difficult right now.
|
||||
|
||||
To show a current example of the bcc Python front-end, here's the code for tracing disk I/O and printing I/O size as a histogram:
|
||||
|
||||
```
|
||||
from bcc import BPF
|
||||
from time import sleep
|
||||
|
||||
# load BPF program
|
||||
b = BPF(text="""
|
||||
#include <uapi/linux/ptrace.h>
|
||||
#include <linux/blkdev.h>
|
||||
|
||||
BPF_HISTOGRAM(dist);
|
||||
|
||||
int kprobe__blk_account_io_completion(struct pt_regs *ctx, struct request *req)
|
||||
{
|
||||
dist.increment(bpf_log2l(req->__data_len / 1024));
|
||||
return 0;
|
||||
}
|
||||
""")
|
||||
|
||||
# header
|
||||
print("Tracing... Hit Ctrl-C to end.")
|
||||
|
||||
# trace until Ctrl-C
|
||||
try:
|
||||
sleep(99999999)
|
||||
except KeyboardInterrupt:
|
||||
print
|
||||
|
||||
# output
|
||||
b["dist"].print_log2_hist("kbytes")
|
||||
|
||||
```
|
||||
|
||||
Note the embedded C (text=) in the Python code.
|
||||
|
||||
This gets the job done, but there's also room for improvement. Fortunately, we have time to do so: it will take many months before people are on Linux 4.9 and can use BPF, so we have time to create tools and front-ends.
|
||||
|
||||
### A higher-level language
|
||||
|
||||
An easier front-end, such as a higher-level language, may not improve adoption as much as you might imagine. Most people will use the canned tools (and GUIs), and only some of us will actually write them. But I'm not opposed to a higher-level language either, and some already exist, like SystemTap:
|
||||
|
||||
```
|
||||
#!/usr/bin/stap
|
||||
/*
|
||||
* opensnoop.stp Trace file open()s. Basic version of opensnoop.
|
||||
*/
|
||||
|
||||
probe begin
|
||||
{
|
||||
printf("\n%6s %6s %16s %s\n", "UID", "PID", "COMM", "PATH");
|
||||
}
|
||||
|
||||
probe syscall.open
|
||||
{
|
||||
printf("%6d %6d %16s %s\n", uid(), pid(), execname(), filename);
|
||||
}
|
||||
|
||||
```
|
||||
|
||||
Wouldn't it be nice if we could have the SystemTap front-end with all its language integration and tapsets, with the high-performance kernel built in BPF back-end? Richard Henderson of Red Hat has already begun work on this, and has released an [initial version][30]!
|
||||
|
||||
There's also [ply][29], an entirely new higher-level language for BPF:
|
||||
|
||||
```
|
||||
#!/usr/bin/env ply
|
||||
|
||||
kprobe:SyS_*
|
||||
{
|
||||
$syscalls[func].count()
|
||||
}
|
||||
|
||||
```
|
||||
|
||||
This is also promising.
|
||||
|
||||
Although, I think the real challenge for tool developers won't be the language: it will be knowing what to do with these new superpowers.
|
||||
|
||||
### How you can contribute
|
||||
|
||||
* **Promotion**: There are currently no marketing efforts for BPF tracing. Some companies know it and are using it (Facebook, Netflix, Github, and more), but it'll take years to become widely known. You can help by sharing articles and resources with others in the industry.
|
||||
* **Education**: You can write articles, give meetup talks, and contribute to bcc documentation. Share case studies of how BPF has solved real issues, and provided value to your company.
|
||||
* **Fix bcc issues**: See the [bcc issue list][19], which includes bugs and feature requests.
|
||||
* **File bugs**: Use bcc/BPF, and file bugs as you find them.
|
||||
* **New tools**: There are more observability tools to develop, but please don't be hasty: people are going to spend hours learning and using your tool, so make it as intuitive and excellent as possible (see my [docs][18]). As Mike Muuss has said about his [ping][17] program: "If I'd known then that it would be my most famous accomplishment in life, I might have worked on it another day or two and added some more options."
|
||||
* **High-level language**: If the existing bcc front-end languages really bother you, maybe you can come up with something much better. If you build it in bcc you can leverage libbcc. Or, you could help the SystemTap BPF or ply efforts.
|
||||
* **GUI integration**: Apart from the bcc CLI observability tools, how can this new information be visualized? Latency heat maps, flame graphs, and more.
|
||||
|
||||
### Other Tracers
|
||||
|
||||
What about SystemTap, ktap, sysdig, LTTng, etc? It's possible that they all have a future, either by using BPF, or by becoming better at what they specifically do. Explaining each will be a blog post by itself.
|
||||
|
||||
And DTrace itself? We're still using it at Netflix, on our FreeBSD-based CDN.
|
||||
|
||||
### Further bcc/BPF Reading
|
||||
|
||||
I've written a [bcc/BPF Tool End-User Tutorial][28], a [bcc Python Developer's Tutorial][27], a [bcc/BPF Reference Guide][26], and contributed useful [/tools][25], each with an [example.txt][24] file and [man page][23]. My prior posts about bcc & BPF include:
|
||||
|
||||
* [eBPF: One Small Step][16] (we later just called it BPF)
|
||||
* [bcc: Taming Linux 4.3+ Tracing Superpowers][15]
|
||||
* [Linux eBPF Stack Trace Hack][14] (stack traces are now officially supported)
|
||||
* [Linux eBPF Off-CPU Flame Graph][13] (" " ")
|
||||
* [Linux Wakeup and Off-Wake Profiling][12] (" " ")
|
||||
* [Linux Chain Graph Prototype][11] (" " ")
|
||||
* [Linux eBPF/bcc uprobes][10]
|
||||
* [Linux BPF Superpowers][9]
|
||||
* [Ubuntu Xenial bcc/BPF][8]
|
||||
* [Linux bcc Tracing Security Capabilities][7]
|
||||
* [Linux MySQL Slow Query Tracing with bcc/BPF][6]
|
||||
* [Linux bcc ext4 Latency Tracing][5]
|
||||
* [Linux bcc/BPF Run Queue (Scheduler) Latency][4]
|
||||
* [Linux bcc/BPF Node.js USDT Tracing][3]
|
||||
* [Linux bcc tcptop][2]
|
||||
* [Linux 4.9's Efficient BPF-based Profiler][1]
|
||||
|
||||
I've also given a talk about bcc/BPF, at Facebook's Performance@Scale event: [Linux BPF Superpowers][22]. In December, I'm giving a tutorial and talk on BPF/bcc at [USENIX LISA][21] in Boston.
|
||||
|
||||
### Acknowledgements
|
||||
|
||||
* Van Jacobson and Steve McCanne, who created the original BPF as a packet filter.
|
||||
* Barton P. Miller, Jeffrey K. Hollingsworth, and Jon Cargille, for inventing dynamic tracing, and publishing the paper: "Dynamic Program Instrumentation for Scalable Performance Tools", Scalable High-performance Conputing Conference (SHPCC), Knoxville, Tennessee, May 1994.
|
||||
* kerninst (ParaDyn, UW-Madison), an early dynamic tracing tool that showed the value of dynamic tracing (late 1990's).
|
||||
* Mathieu Desnoyers (of LTTng), the lead developer of kernel markers that led to tracepoints.
|
||||
* IBM developed kprobes as part of DProbes. DProbes was combined with LTT to provide Linux dynamic tracing in 2000, but wasn't integrated.
|
||||
* Bryan Cantrill, Mike Shapiro, and Adam Leventhal (Sun Microsystems), the core developers of DTrace, an awesome tool which proved that dynamic tracing could be production safe and easy to use (2004). Given the mechanics of dynamic tracing, this was a crucial turning point for the technology: that it became safe enough to be shipped _by default in Solaris_, an OS known for reliability.
|
||||
* The many Sun Microsystems staff in marketing, sales, training, and other roles, for promoting DTrace and creating the awareness and desire for advanced system tracing.
|
||||
* Roland McGrath (at Red Hat), the lead developer of utrace, which became uprobes.
|
||||
* Alexei Starovoitov (PLUMgrid, then Facebook), the lead developer of enhanced BPF: the programmatic kernel components necessary.
|
||||
* Many other Linux kernel engineers who contributed feedback, code, testing, and their own patchsets for the development of enhanced BPF (search lkml for BPF): Wang Nan, Daniel Borkmann, David S. Miller, Peter Zijlstra, and many others.
|
||||
* Brenden Blanco (PLUMgrid), the lead developer of bcc.
|
||||
* Sasha Goldshtein (Sela) developed tracepoint support in bcc, developed the most powerful bcc multitools trace and argdist, and contributed to USDT support.
|
||||
* Vicent Martí and others at Github engineering, for developing the lua front-end for bcc, and contributing parts of USDT.
|
||||
* Allan McAleavy, Mark Drayton, and other bcc contributors for various improvements.
|
||||
|
||||
Thanks to Netflix for providing the environment and support where I've been able to contribute to BPF and bcc tracing, and help get them done. I've also contributed to tracing in general over the years by developing tracing tools (using TNF/prex, DTrace, SystemTap, ktap, ftrace, perf, and now bcc/BPF), and books, blogs, and talks.
|
||||
|
||||
Finally, thanks to [Deirdré][20] for editing another post.
|
||||
|
||||
### Conclusion
|
||||
|
||||
Linux doesn't have DTrace (the language), but it now does, in a way, have the DTraceToolkit (the tools).
|
||||
|
||||
The Linux 4.9 kernel has the final capabilities needed to support modern tracing, via enhancments to its built-in BPF engine. The hardest part is now done: kernel support. Future work now includes more performance CLI tools, alternate higher-level languages, and GUIs.
|
||||
|
||||
For customers of performance analysis products, this is also good news: you can now ask for latency histograms and heatmaps, CPU and off-CPU flame graphs, better latency breakdowns, and lower-cost instrumentation. Per-packet tracing and processing in user space is now the old inefficient way.
|
||||
|
||||
So when are you going to upgrade to Linux 4.9? Once it is officially released, new performance tools await: apt-get install bcc-tools.
|
||||
|
||||
Enjoy!
|
||||
|
||||
Brendan
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: http://www.brendangregg.com/blog/2016-10-27/dtrace-for-linux-2016.html
|
||||
|
||||
作者：[Brendan Gregg][a]
|
||||
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:http://www.brendangregg.com/
|
||||
[1]:http://www.brendangregg.com/blog/2016-10-21/linux-efficient-profiler.html
|
||||
[2]:http://www.brendangregg.com/blog/2016-10-15/linux-bcc-tcptop.html
|
||||
[3]:http://www.brendangregg.com/blog/2016-10-12/linux-bcc-nodejs-usdt.html
|
||||
[4]:http://www.brendangregg.com/blog/2016-10-08/linux-bcc-runqlat.html
|
||||
[5]:http://www.brendangregg.com/blog/2016-10-06/linux-bcc-ext4dist-ext4slower.html
|
||||
[6]:http://www.brendangregg.com/blog/2016-10-04/linux-bcc-mysqld-qslower.html
|
||||
[7]:http://www.brendangregg.com/blog/2016-10-01/linux-bcc-security-capabilities.html
|
||||
[8]:http://www.brendangregg.com/blog/2016-06-14/ubuntu-xenial-bcc-bpf.html
|
||||
[9]:http://www.brendangregg.com/blog/2016-03-05/linux-bpf-superpowers.html
|
||||
[10]:http://www.brendangregg.com/blog/2016-02-08/linux-ebpf-bcc-uprobes.html
|
||||
[11]:http://www.brendangregg.com/blog/2016-02-05/ebpf-chaingraph-prototype.html
|
||||
[12]:http://www.brendangregg.com/blog/2016-02-01/linux-wakeup-offwake-profiling.html
|
||||
[13]:http://www.brendangregg.com/blog/2016-01-20/ebpf-offcpu-flame-graph.html
|
||||
[14]:http://www.brendangregg.com/blog/2016-01-18/ebpf-stack-trace-hack.html
|
||||
[15]:http://www.brendangregg.com/blog/2015-09-22/bcc-linux-4.3-tracing.html
|
||||
[16]:http://www.brendangregg.com/blog/2015-05-15/ebpf-one-small-step.html
|
||||
[17]:http://ftp.arl.army.mil/~mike/ping.html
|
||||
[18]:https://github.com/iovisor/bcc/blob/master/CONTRIBUTING-SCRIPTS.md
|
||||
[19]:https://github.com/iovisor/bcc/issues
|
||||
[20]:http://www.brendangregg.com/blog/2016-07-23/deirdre.html
|
||||
[21]:https://www.usenix.org/conference/lisa16
|
||||
[22]:http://www.brendangregg.com/blog/2016-03-05/linux-bpf-superpowers.html
|
||||
[23]:https://github.com/iovisor/bcc/tree/master/man/man8
|
||||
[24]:https://github.com/iovisor/bcc/tree/master/tools
|
||||
[25]:https://github.com/iovisor/bcc/tree/master/tools
|
||||
[26]:https://github.com/iovisor/bcc/blob/master/docs/reference_guide.md
|
||||
[27]:https://github.com/iovisor/bcc/blob/master/docs/tutorial_bcc_python_developer.md
|
||||
[28]:https://github.com/iovisor/bcc/blob/master/docs/tutorial.md
|
||||
[29]:https://wkz.github.io/ply/
|
||||
[30]:https://lkml.org/lkml/2016/6/14/749
|
||||
[31]:http://www.brendangregg.com/blog/2016-03-30/working-at-netflix-2016.html
|
||||
[32]:http://www.slideshare.net/brendangregg/from-dtrace-to-linux
|
||||
[33]:https://lkml.org/lkml/2016/9/1/831
|
||||
[34]:https://github.com/brendangregg/perf-tools
|
||||
[35]:https://github.com/iovisor/bcc/blob/master/INSTALL.md
|
||||
[36]:https://github.com/iovisor/bcc
|
||||
[37]:https://github.com/opendtrace/toolkit
|
||||
[38]:https://raw.githubusercontent.com/brendangregg/bcc/master/images/bcc_tracing_tools_2016.png
|
||||
@ -0,0 +1,115 @@
|
||||
3 Ways to Extract and Copy Files from ISO Image in Linux
|
||||
============================================================
|
||||
|
||||
Let’s say you have a large ISO file on your Linux server and you wanted to access, extract or copy one single file from it. How do you do it? Well in Linux there are couple ways do it.
|
||||
|
||||
For example, you can use standard mount command to mount an ISO image in read-only mode using the loop device and then copy the files to another directory.
|
||||
|
||||
### Mount or Extract ISO File in Linux
|
||||
|
||||
To do so, you must have an ISO file (I used ubuntu-16.10-server-amd64.iso ISO image) and mount point directory to mount or extract ISO files.
|
||||
|
||||
First create an mount point directory, where you will going to mount the image as shown:
|
||||
|
||||
```
|
||||
$ sudo mkdir /mnt/iso
|
||||
```
|
||||
|
||||
Once directory has been created, you can easily mount ubuntu-16.10-server-amd64.iso file and verify its content by running following command.
|
||||
|
||||
```
|
||||
$ sudo mount -o loop ubuntu-16.10-server-amd64.iso /mnt/iso
|
||||
$ ls /mnt/iso/
|
||||
```
|
||||
[
|
||||
|
||||
][1]
|
||||
|
||||
Mount ISO File in Linux
|
||||
|
||||
Now you can go inside the mounted directory (/mnt/iso) and access the files or copy the files to `/tmp`directory using [cp command][2].
|
||||
|
||||
```
|
||||
$ cd /mnt/iso
|
||||
$ sudo cp md5sum.txt /tmp/
|
||||
$ sudo cp -r ubuntu /tmp/
|
||||
```
|
||||
[
|
||||
|
||||
][3]
|
||||
|
||||
Copy Files From ISO File in Linux
|
||||
|
||||
Note: The `-r` option used to copy directories recursively, if you want you can also [monitor progress of copy command][4].
|
||||
|
||||
### Extract ISO Content Using 7zip Command
|
||||
|
||||
If you don’t want to mount ISO file, you can simply install 7zip, is an open source archive program used to pack or unpack different number of formats including TAR, XZ, GZIP, ZIP, BZIP2, etc..
|
||||
|
||||
```
|
||||
$ sudo apt-get install p7zip-full p7zip-rar [On Debian/Ubuntu systems]
|
||||
$ sudo yum install p7zip p7zip-plugins [On CentOS/RHEL systems]
|
||||
```
|
||||
|
||||
Once 7zip program has been installed, you can use 7z command to extract ISO file contents.
|
||||
|
||||
```
|
||||
$ 7z x ubuntu-16.10-server-amd64.iso
|
||||
```
|
||||
[
|
||||
|
||||
][5]
|
||||
|
||||
7zip – Extract ISO File Content in Linux
|
||||
|
||||
Note: As compared to Linux mount command, 7zip seems much faster and smart enough to pack or unpack any archive formats.
|
||||
|
||||
### Extract ISO Content Using isoinfo Command
|
||||
|
||||
The isoinfo command is used for directory listings of iso9660 images, but you can also use this program to extract files.
|
||||
|
||||
As I said isoinfo program perform directory listing, so first list the content of ISO file.
|
||||
|
||||
```
|
||||
$ isoinfo -i ubuntu-16.10-server-amd64.iso -l
|
||||
```
|
||||
[
|
||||
|
||||
][6]
|
||||
|
||||
List ISO Content in Linux
|
||||
|
||||
Now you can extract a single file from an ISO image like so:
|
||||
|
||||
```
|
||||
$ isoinfo -i ubuntu-16.10-server-amd64.iso -x MD5SUM.TXT > MD5SUM.TXT
|
||||
```
|
||||
|
||||
Note: The redirection is needed as `-x` option extracts to stdout.
|
||||
|
||||
[
|
||||
|
||||
][7]
|
||||
|
||||
Extract Single File from ISO in Linux
|
||||
|
||||
Well, there are many ways to do, if you know any useful command or program to extract or copy files from ISO file do share us via comment section.
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: http://www.tecmint.com/extract-files-from-iso-files-linux
|
||||
|
||||
作者：[Ravi Saive][a]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:http://www.tecmint.com/author/admin/
|
||||
[1]:http://www.tecmint.com/wp-content/uploads/2016/10/Mount-ISO-File-in-Linux.png
|
||||
[2]:http://www.tecmint.com/advanced-copy-command-shows-progress-bar-while-copying-files/
|
||||
[3]:http://www.tecmint.com/wp-content/uploads/2016/10/Copy-Files-From-ISO-File-in-Linux.png
|
||||
[4]:http://www.tecmint.com/monitor-copy-backup-tar-progress-in-linux-using-pv-command/
|
||||
[5]:http://www.tecmint.com/wp-content/uploads/2016/10/Extract-ISO-Content-in-Linux.png
|
||||
[6]:http://www.tecmint.com/wp-content/uploads/2016/10/List-ISO-Content-in-Linux.png
|
||||
[7]:http://www.tecmint.com/wp-content/uploads/2016/10/Extract-Single-File-from-ISO-in-Linux.png
|
||||
@ -0,0 +1,106 @@
|
||||
translating by chenzhijun
|
||||
|
||||
HOW TO CREATE AN EBOOK WITH CALIBRE IN LINUX [COMPLETE GUIDE]
|
||||
====
|
||||
|
||||
|
||||
[][8]
|
||||
|
||||
_Brief: This beginner’s guide shows you how to quickly create an ebook with Calibre tool in Linux._
|
||||
|
||||
Ebooks have been growing by leaps and bounds in popularity since Amazon started selling them several years ago. The good news is that they are very easy to create with Free and Open Source tools.
|
||||
|
||||
In this tutorial, I’ll show you how to create an eBook in Linux.
|
||||
|
||||
### CREATING AN EBOOK IN LINUX
|
||||
|
||||
To create an ebook you’ll need two pieces of software: a word processor (I’ll be using [LibreOffice][7], of course) and Calibre. [Calibre][6]is a great ebook reader and library program. You can use it to [open ePub files in Linux][5] or to manage your collection of eBooks.
|
||||
|
||||
Besides this software, you also need an ebook cover (1410×2250) and your manuscript.
|
||||
|
||||
### STEP 1
|
||||
|
||||
First, you need to open your manuscript with your word processor. Calibre can automatically create a table of contents for you. In order to do so, you need to set the chapter titles into your manuscript to Heading 1\. Just highlight the chapter titles and selection “Heading 1” from the paragraph style drop down box.
|
||||
|
||||
|
||||
|
||||
If you plan to have sub-chapters and want them to be added to the TOC, then make all those titles Heading 2.
|
||||
|
||||
Now, save your document as an HTML file.
|
||||
|
||||
### STEP 2
|
||||
|
||||
In Calibre, click the “Add books” button. After the dialog box appears, you can browse to where your HTML file is located and add it to the program.
|
||||
|
||||
|
||||
|
||||
### STEP 3
|
||||
|
||||
Once the new HTML file is added to the Calibre library, select the new file and click the “Edit metadata” button. From here you can add the following information: Title, Author, cover image, description and more. When you’re done, click “OK”.
|
||||
|
||||
|
||||
|
||||
### STEP 4
|
||||
|
||||
Now click the “Convert books” button.
|
||||
|
||||
In the new windows, there are quite a few options available, but you don’t need to use them all.
|
||||
|
||||
[Suggested ReadFix Pear Updater Issue In Pear OS 8][4]
|
||||
|
||||
|
||||
|
||||
From the top right of the new screen, you select epub. Calibre also gives your the option to create a mobi file, but I found that those files didn’t always work the way I wanted them to.
|
||||
|
||||
|
||||
|
||||
### STEP 5
|
||||
|
||||
Click the “Look & Feel” tab from the left side of the new dialog box. Now, select the “Remove spacing between paragraphs”.
|
||||
|
||||
|
||||
|
||||
Next, we will create the table of contents. If don’t plan to use a table of contents in your book, you skip this step. Select the Table of Contents tab. From there, click on the select the wand icon to the right of “Level 1 TOC (XPath expression)”.
|
||||
|
||||
|
||||
|
||||
In the new window, select “h1” from the drop down menu under “Match HTML tags with tag name”. Click “OK” to close the window. If you set up sub-chapters, set the “Level 2 TOC (XPath expression)” to h2.
|
||||
|
||||
|
||||
|
||||
Before we start the conversion, select EPUB Output. On the new page, select the “Insert inline Table of Contents” option.
|
||||
|
||||
|
||||
|
||||
Now all you have to do is click “OK” to start the conversion process. Unless you have a huge file, the conversion should finish fairly quickly.
|
||||
|
||||
There you go, you just created a quick ebook
|
||||
|
||||
For the more advanced users who know how to write CSS, Calibre gives your the option to add CSS styling to your text. Just go to the “Look & Feel” section and select the styling tab. If you try to do this with mobi, it won’t accept all of the styling for some reason.
|
||||
|
||||
|
||||
|
||||
Well, that was fairly easy, isn’t it? I hope this tutorial helped you to create eBooks in Linux.
|
||||
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://itsfoss.com/create-ebook-calibre-linux/
|
||||
|
||||
作者：[John Paul ][a]
|
||||
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]: https://itsfoss.com/author/john/
|
||||
[1]:http://pinterest.com/pin/create/button/?url=https://itsfoss.com/create-ebook-calibre-linux/&description=How+To+Create+An+Ebook+With+Calibre+In+Linux+%5BComplete+Guide%5D&media=https://itsfoss.com/wp-content/uploads/2016/10/Create-an-eBook-in-Linux.jpg
|
||||
[2]:https://www.linkedin.com/cws/share?url=https://itsfoss.com/create-ebook-calibre-linux/
|
||||
[3]:https://twitter.com/share?original_referer=https%3A%2F%2Fitsfoss.com%2F&source=tweetbutton&text=How+To+Create+An+Ebook+With+Calibre+In+Linux+%5BComplete+Guide%5D&url=https%3A%2F%2Fitsfoss.com%2Fcreate-ebook-calibre-linux%2F&via=%40itsfoss
|
||||
[4]:https://itsfoss.com/fix-updater-issue-pear-os-8/
|
||||
[5]:https://itsfoss.com/open-epub-books-ubuntu-linux/
|
||||
[6]:http://calibre-ebook.com/
|
||||
[7]:https://www.libreoffice.org/
|
||||
[8]:https://itsfoss.com/wp-content/uploads/2016/10/Create-an-eBook-in-Linux.jpg
|
||||
@ -0,0 +1,100 @@
|
||||
4 Useful Way to Know Plugged USB Device Name in Linux
|
||||
============================================================
|
||||
|
||||
As a newbie, one of the many [things you should master in Linux][1] is identification of devices attached to your system. It may be your computer’s hard disk, an external hard drive or removable media such USB drive or SD Memory card.
|
||||
|
||||
Using USB drives for file transfer is so common today, and for those (new Linux users) who prefer to use the command line, learning the different ways to identify a USB device name is very important, when you need to format it.
|
||||
|
||||
Once you attach a device to your system such as a USB, especially on a desktop, it is automatically mounted to a given directory, normally under /media/username/device-label and you can then access the files in it from that directory. However, this is not the case with a server where you have to[ manually mount a device][2] and specify its mount point.
|
||||
|
||||
Linux identifies devices using special device files stored in `/dev` directory. Some of the files you will find in this directory include `/dev/sda` or `/dev/hda` which represents your first master drive, each partition will be represented by a number such as `/dev/sda1` or `/dev/hda1` for the first partition and so on.
|
||||
|
||||
```
|
||||
$ ls /dev/sda*
|
||||
```
|
||||
[
|
||||
|
||||
][3]
|
||||
|
||||
List All Linux Device Names
|
||||
|
||||
Now let’s find out device names using some different command-line tools as shown:
|
||||
|
||||
### Find Out Plugged USB Device Name Using df Command
|
||||
|
||||
To view each device attached to your system as well as its mount point, you can use the [df command][4](checks Linux disk space utilization) as shown in the image below:
|
||||
|
||||
```
|
||||
$ df -h
|
||||
```
|
||||
[
|
||||
|
||||
][5]
|
||||
|
||||
Find USB Device Name Using df Command
|
||||
|
||||
### Use lsblk Command to Find USB Device Name
|
||||
|
||||
You can also use the [lsblk command (list block devices)][6] which lists all block devices attached to your system like so:
|
||||
|
||||
```
|
||||
$ lsblk
|
||||
```
|
||||
[
|
||||
|
||||
][7]
|
||||
|
||||
List Linux Block Devices
|
||||
|
||||
### Identify USB Device Name with fdisk Utility
|
||||
|
||||
[fdisk is a powerful utility][8] which prints out the partition table on all your block devices, a USB drive inclusive, you can run it will root privileges as follows:
|
||||
|
||||
```
|
||||
$ sudo fdisk -l
|
||||
```
|
||||
[
|
||||
|
||||
][9]
|
||||
|
||||
List Partition Table of Block Devices
|
||||
|
||||
### Determine USB Device Name with dmesg Command
|
||||
|
||||
dmesg is an important command that prints or controls the kernel ring buffer, a data structure which [stores information about the kernel’s operations][10].
|
||||
|
||||
Run the command below to view kernel operation messages which will as well print information about your USB device:
|
||||
|
||||
```
|
||||
$ dmesg
|
||||
```
|
||||
[
|
||||
|
||||
][11]
|
||||
|
||||
dmesg – Prints USB Device Name
|
||||
|
||||
That is all for now, in this article, we have covered different approaches of how to find out a USB device name from the command line. You can also share with us any other methods for the same purpose or perhaps offer us your thoughts about the article via the response section below.
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: http://www.tecmint.com/find-usb-device-name-in-linux
|
||||
|
||||
作者：[Aaron Kili ][a]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:http://www.tecmint.com/author/aaronkili/
|
||||
[1]:http://www.tecmint.com/tag/linux-tricks/
|
||||
[2]:http://www.tecmint.com/mount-filesystem-in-linux/
|
||||
[3]:http://www.tecmint.com/wp-content/uploads/2016/10/List-All-Linux-Device-Names.png
|
||||
[4]:http://www.tecmint.com/how-to-check-disk-space-in-linux/
|
||||
[5]:http://www.tecmint.com/wp-content/uploads/2016/10/Find-USB-Device-Name.png
|
||||
[6]:http://www.tecmint.com/commands-to-collect-system-and-hardware-information-in-linux/
|
||||
[7]:http://www.tecmint.com/wp-content/uploads/2016/10/List-Linux-Block-Devices.png
|
||||
[8]:http://www.tecmint.com/fdisk-commands-to-manage-linux-disk-partitions/
|
||||
[9]:http://www.tecmint.com/wp-content/uploads/2016/10/List-Partition-Table.png
|
||||
[10]:http://www.tecmint.com/dmesg-commands/
|
||||
[11]:http://www.tecmint.com/wp-content/uploads/2016/10/dmesg-shows-kernel-information.png
|
||||
@ -1,3 +1,5 @@
|
||||
【翻译中】 by jayjay823
|
||||
|
||||
# 5 Best FPS Games For Linux
|
||||
|
||||
|
||||
|
||||
@ -1,3 +1,5 @@
|
||||
Vic020
|
||||
|
||||
# How to design and add your own font on Linux with Glyphr
|
||||
|
||||
LibreOffice already offers a galore of fonts, and users can always download and add more. However, if you want to create your own custom font, you can do it easily by using Glyphr. Glyphr is a new open source vector font designer with an intuitive and easy to use graphical interface and a rich set of features that will take care every aspect of the font design. Although the application is still in early development, it is already pretty good. Here’s a quick guide showing how to design your own custom fonts on Glyphr, and how to add them on LibreOffice once you’re done.
|
||||
|
||||
@ -0,0 +1,109 @@
|
||||
CLOUD FOCUSED LINUX DISTROS FOR PEOPLE WHO BREATHE ONLINE
|
||||
============================================================
|
||||
|
||||
[
|
||||
|
||||
][6]
|
||||
|
||||
_Brief: We list some _Cloud centric_ Linux distributions that might be termed as real Linux alternatives to Chrome OS._
|
||||
|
||||
The world is moving to cloud-based services and we all know the kind of love that Chrome OS got. Well, it does deserve respect. It’s super fast, light, power-efficient, minimalistic, beautifully designed and utilizes the full potential of cloud that technology permits today.
|
||||
|
||||
Although [Chrome OS][7] is exclusively available only for Google’s hardware, there are other means to experience the potential of cloud computing right on your laptop or desktop.
|
||||
|
||||
As I have repeatedly said, there is always something for everybody in the Linux domain, be it [Linux distributions that look like Windows][8] or Mac OS. Linux is all about sharing, love and some really bleeding edge computing experience. Let’s crack this list right away!
|
||||
|
||||
### 1\. CUB LINUX
|
||||
|
||||
|
||||
|
||||
It is not Chrome OS. But the above image is featuring the desktop of [Cub Linux][9]. Say what?
|
||||
|
||||
Cub Linux is no news for Linux users. But if you already did not know, Cub Linux is the web focused Linux distro that is inspired from mainstream Chrome OS. It is also the open source brother of Chrome OS from mother Linux.
|
||||
|
||||
Chrome OS has the Chrome Browser as it’s primary component. Not so long ago, a project by name [Chromixium OS][10] was started to recreate Chrome OS like experience by using the Chromium Browser in place of Chrome Browser. Due to some legal issues, the name was later changed to Cub Linux (Chromium+Ubuntu).
|
||||
|
||||
|
||||
|
||||
Well, history apart, as the name hints, Cub Linux is based on Ubuntu, features the lightweight Openbox Desktop Environment. The Desktop is customized to give a Chrome OS impression and looks really neat.
|
||||
|
||||
In the apps department, you can install the web applications from the Chrome web store and all the Ubuntu software. Yup, with all the snappy apps of the Chrome OS, You’ll still get the Ubuntu goodies.
|
||||
|
||||
As far as the performance is concerned, the operating system is super fast thanks to its Openbox Desktop Environment. Based on Ubuntu Linux, the stability of Cub Linux is unquestionable. The desktop itself is a treat to the eyes with all its smooth animations and beautiful UI.
|
||||
|
||||
[Suggested Read[Year 2013 For Linux] 2 Linux Distributions Discontinued][11]
|
||||
|
||||
I suggest Cub Linux to anybody who spends most their times on a browser and do some home tasks now and then. Well, a browser is all you need and a browser is exactly what you’ll get.
|
||||
|
||||
### 2\. PEPPERMINT OS
|
||||
|
||||
A good number of people look towards Linux because they want a no-BS computing experience. Some people do not really like the hassle of an anti-virus, a defragmenter, a cleaner etcetera as they want an operating system and not a baby. And I must say Peppermint OS is really good at being no-BS. [Peppermint OS][12] developers have put a good amount of effort in understanding the user requirements and needs.
|
||||
|
||||
|
||||
|
||||
There is a very small number of selected software included by default. The traditional ideology of including a couple apps from every software category is ditched here for good. The power to customize the computer as per needs has been given to the user. By the way, do we really need to install so many applications when we can get web alternatives for almost all the applications?
|
||||
|
||||
Ice
|
||||
|
||||
Ice is a utile little tool that converts your favorite and most used websites into desktop applications that you can directly launch from your desktop or the menu. It’s what we call a site-specific browser.
|
||||
|
||||
|
||||
|
||||
Love facebook? Why not make a facebook web app on your desktop for quick launch? While there are people complaining about a decent Google drive application for Linux, Ice allows you to access Drive with just a click. Not just Drive, the functionality of Ice is limited only by your imagination.
|
||||
|
||||
Peppermint OS 7 is based on Ubuntu 16.04\. It not only provides a smooth, rock solid performance but also a very swift response. A heavily customizes LXDE will be your home screen. And the customization I’m speaking about is driven to achieve both a snappy performance as well as visual appeal.
|
||||
|
||||
Peppermint OS hits more of a middle ground in the cloud-native operating system types. Although the skeleton of the OS is designed to support the speedy cloudy apps, the native Ubuntu application play well too. If you are someone like me who wants an OS that is balanced in online-offline capabilities, [Peppermint OS is for you][13].
|
||||
|
||||
[Suggested ReadPennsylvania High School Distributes 1,700 Ubuntu Laptops to Students][14]
|
||||
|
||||
### 3.APRICITY OS
|
||||
|
||||
[Apricity OS][15] stole the show for being one of the top aesthetically pleasing Linux distros out there. It’s just gorgeous. It’s like the Mona Lisa of the Linux domain. But, there’s more to it than just the looks.
|
||||
|
||||
|
||||
|
||||
The prime reason [Apricity OS][16] makes this list is because of its simplicity. While OS desktop design is getting chaotic and congested with elements (and I’m not talking only about non-Linux operating systems), Apricity de-clutters everything and simplifies the very basic human-desktop interaction. Gnome desktop environment is customized beautifully here. They made it really simpler.
|
||||
|
||||
The pre-installed software list is really small. Almost all Linux distros have the same pre-installed software. But Apricity OS has a completely new set of software. Chrome instead of Firefox. I was really waiting for this. I mean why not give us what’s rocking out there?
|
||||
|
||||
Apricity OS also features the Ice tool that we discussed in the last segment. But instead of Firefox, Chrome browser is used in website-desktop integration. Apricity OS has Numix Circle icons by default and everytime you add a popular webapp, there will be a beautiful icon placed on your Dock.
|
||||
|
||||
|
||||
|
||||
See what I mean?
|
||||
|
||||
Apricity OS is based on Arch Linux. (So anybody looking for a quick start with Arch, and a beautiful at that one, download that Apricity ISO [here][17]) Apricity fully upholds the Arch principle of freedom of choice. Within just 10 minutes on the Ice, and you’ll have all your favorite webapps set up.
|
||||
|
||||
Gorgeous backgrounds, minimalistic desktop and a great functionality. These make Apricity OS a really great choice for setting up an amazing cloud-centric system. It’ll take 5 mins for Apricity OS to make you fall in love with it. I mean it.
|
||||
|
||||
There you have it, people. Cloud-centric Linux distros for online dwellers. Do give us your take on the webapp-native app topic. Don’t forget to share.
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://itsfoss.com/cloud-focused-linux-distros/
|
||||
|
||||
作者：[Aquil Roshan ][a]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:https://itsfoss.com/author/aquil/
|
||||
[1]:https://itsfoss.com/author/aquil/
|
||||
[2]:https://itsfoss.com/cloud-focused-linux-distros/#comments
|
||||
[3]:https://twitter.com/share?original_referer=https%3A%2F%2Fitsfoss.com%2F&source=tweetbutton&text=Cloud+Focused+Linux+Distros+For+People+Who+Breathe+Online&url=https%3A%2F%2Fitsfoss.com%2Fcloud-focused-linux-distros%2F&via=%40itsfoss
|
||||
[4]:https://www.linkedin.com/cws/share?url=https://itsfoss.com/cloud-focused-linux-distros/
|
||||
[5]:http://pinterest.com/pin/create/button/?url=https://itsfoss.com/cloud-focused-linux-distros/&description=Cloud+Focused+Linux+Distros+For+People+Who+Breathe+Online&media=https://itsfoss.com/wp-content/uploads/2016/11/cloud-centric-Linux-distributions.jpg
|
||||
[6]:https://itsfoss.com/wp-content/uploads/2016/11/cloud-centric-Linux-distributions.jpg
|
||||
[7]:https://en.wikipedia.org/wiki/Chrome_OS
|
||||
[8]:https://itsfoss.com/windows-like-linux-distributions/
|
||||
[9]:https://cublinux.com/
|
||||
[10]:https://itsfoss.com/chromixiumos-released/
|
||||
[11]:https://itsfoss.com/year-2013-linux-2-linux-distributions-discontinued/
|
||||
[12]:https://peppermintos.com/
|
||||
[13]:https://peppermintos.com/
|
||||
[14]:https://itsfoss.com/pennsylvania-high-school-ubuntu/
|
||||
[15]:https://apricityos.com/
|
||||
[16]:https://itsfoss.com/apricity-os/
|
||||
[17]:https://apricityos.com/
|
||||
@ -1,3 +1,5 @@
|
||||
Translating by rusking
|
||||
|
||||
# Kali Linux – Fresh Installation Guide
|
||||
|
||||
Kali Linux is arguably one of the best out of the box [Linux distributions available for security testing][18]. While many of the tools in Kali can be installed in most Linux distributions, the Offensive Security team developing Kali has put countless hours into perfecting their ready to boot security distribution.
|
||||
|
||||
@ -1,249 +0,0 @@
|
||||
DockerChen翻译中
|
||||
|
||||
# A Practical Guide to Nmap (Network Security Scanner) in Kali Linux
|
||||
|
||||
In the second Kali Linux article, the network tool known as ‘[nmap][30]‘ will be discussed. While nmap isn’t a Kali only tool, it is one of the most [useful network mapping tools][29] in Kali.
|
||||
|
||||
1. [Kali Linux Installation Guide for Beginners – Part 1][4]
|
||||
|
||||
Nmap, short for Network Mapper, is maintained by Gordon Lyon (more about Mr. Lyon here: [http://insecure.org/fyodor/][28]) and is used by many security professionals all over the world.
|
||||
|
||||
The utility works in both Linux and Windows and is command line (CLI) driven. However for those a little more timid of the command line, there is a wonderful graphical frontend for nmap called zenmap.
|
||||
|
||||
It is strongly recommended that individuals learn the CLI version of nmap as it provides much more flexibility when compared to the zenmap graphical edition.
|
||||
|
||||
What purpose does nmap server? Great question. Nmap allows for an administrator to quickly and thoroughly learn about the systems on a network, hence the name, Network MAPper or nmap.
|
||||
|
||||
Nmap has the ability to quickly locate live hosts as well as services associated with that host. Nmap’s functionality can be extended even further with the Nmap Scripting Engine, often abbreviated as NSE.
|
||||
|
||||
This scripting engine allows administrators to quickly create a script that can be used to determine if a newly discovered vulnerability exists on their network. Many scripts have been developed and included with most nmap installs.
|
||||
|
||||
A word of caution – nmap is a commonly used by people with both good and bad intentions. Extreme caution should be taken to ensure that you aren’t using nmap against systems that permission has not be explicitlyprovided in a written/legal agreement. Please use caution when using the nmap tool.
|
||||
|
||||
#### System Requirements
|
||||
|
||||
1. [Kali Linux][3] (nmap is available in other operating systems and functions similar to this guide).
|
||||
2. Another computer and permission to scan that computer with nmap – This is often easily done with software such as [VirtualBox][2] and the creation of a virtual machine.
|
||||
1. For a good machine to practice with, please read about Metasploitable 2
|
||||
2. Download for MS2 [Metasploitable2][1]
|
||||
3. A valid working connection to a network or if using virtual machines, a valid internal network connection for the two machines.
|
||||
|
||||
### Kali Linux – Working with Nmap
|
||||
|
||||
The first step to working with nmap is to log into the Kali Linux machine and if desired, start a graphical session (This first article in this series installed [Kali Linux with the Enlightenment Desktop Environment][27]).
|
||||
|
||||
During the installation, the installer would have prompted the user for a ‘root‘ user password which will be needed to login. Once logged in to the Kali Linux machine, using the command ‘startx‘ the Enlightenment Desktop Environment can be started – it is worth noting that nmap doesn’t require a desktop environment to run.
|
||||
|
||||
```
|
||||
# startx
|
||||
|
||||
```
|
||||
[
|
||||
|
||||
][26]
|
||||
|
||||
Start Desktop Environment in Kali Linux
|
||||
|
||||
Once logged into Enlightenment, a terminal window will need to be opened. By clicking on the desktop background, a menu will appear. Navigating to a terminal can be done as follows: Applications -> System ->‘Xterm‘ or ‘UXterm‘ or ‘Root Terminal‘.
|
||||
|
||||
The author is a fan of the shell program called ‘[Terminator][25]‘ but this may not show up in a default install of Kali Linux. All shell programs listed will work for the purposes of nmap.
|
||||
|
||||
[
|
||||
|
||||
][24]
|
||||
|
||||
Launch Terminal in Kali Linux
|
||||
|
||||
Once a terminal has been launched, the nmap fun can begin. For this particular tutorial, a private network with a Kali machine and a Metasploitable machine was created.
|
||||
|
||||
This made things easier and safer since the private network range would ensure that scans remained on safe machines and prevents the vulnerable Metasploitable machine from being compromised by someone else.
|
||||
|
||||
In this example, both of the machines are on a private 192.168.56.0 /24 network. The Kali machine has an IP address of 192.168.56.101 and the Metasploitable machine to be scanned has an IP address of 192.168.56.102.
|
||||
|
||||
Let’s say though that the IP address information was unavailable. A quick nmap scan can help to determine what is live on a particular network. This scan is known as a ‘Simple List’ scan hence the `-sL` arguments passed to the nmap command.
|
||||
|
||||
```
|
||||
# nmap -sL 192.168.56.0/24
|
||||
|
||||
```
|
||||
[
|
||||
|
||||
][23]
|
||||
|
||||
Nmap – Scan Network for Live Hosts
|
||||
|
||||
Sadly, this initial scan didn’t return any live hosts. Sometimes this is a factor of the way certain Operating Systems handle [port scan network traffic][22].
|
||||
|
||||
Not to worry though, there are some tricks that nmap has available to try to find these machines. This next trick will tell nmap to simply try to ping all the addresses in the 192.168.56.0/24 network.
|
||||
|
||||
```
|
||||
# nmap -sn 192.168.56.0/24
|
||||
|
||||
```
|
||||
[
|
||||
|
||||
][21]
|
||||
|
||||
Nmap – Ping All Connected Live Network Hosts
|
||||
|
||||
This time nmap returns some prospective hosts for scanning! In this command, the `-sn` disables nmap’s default behavior of attempting to port scan a host and simply has nmap try to ping the host.
|
||||
|
||||
Let’s try letting nmap port scan these specific hosts and see what turns up.
|
||||
|
||||
```
|
||||
# nmap 192.168.56.1,100-102
|
||||
|
||||
```
|
||||
[
|
||||
|
||||
][20]
|
||||
|
||||
Nmap – Network Ports Scan on Host
|
||||
|
||||
Wow! This time nmap hit a gold mine. This particular host has quite a bit of [open network ports][19].
|
||||
|
||||
These ports all indicate some sort of listening service on this particular machine. Recalling from earlier, the 192.168.56.102 IP address is assigned to the metasploitable vulnerable machine hence why there are so many [open ports on this host][18].
|
||||
|
||||
Having this many ports open on most machines is highly abnormal so it may be a wise idea to investigate this machine a little closer. Administrators could track down the physical machine on the network and look at the machine locally but that wouldn’t be much fun especially when nmap could do it for us much quicker!
|
||||
|
||||
This next scan is a service scan and is often used to try to determine what [service may be listening on a particular port][17] on a machine.
|
||||
|
||||
Nmap will probe all of the open ports and attempt to banner grab information from the services running on each port.
|
||||
|
||||
```
|
||||
# nmap -sV 192.168.56.102
|
||||
|
||||
```
|
||||
[
|
||||
|
||||
][16]
|
||||
|
||||
Nmap – Scan Network Services Listening of Ports
|
||||
|
||||
Notice this time nmap provided some suggestions on what nmap thought might be running on this particular port (highlighted in the white box). Also nmap also tried to [determine information about the operating system][15]running on this machine as well as its hostname (with great success too!).
|
||||
|
||||
Looking through this output should raise quite a few concerns for a network administrator. The very first line claims that VSftpd version 2.3.4 is running on this machine! That’s a REALLY old version of VSftpd.
|
||||
|
||||
Searching through ExploitDB, a serious vulnerability was found back in 2011 for this particular version (ExploitDB ID – 17491).
|
||||
|
||||
Let’s have nmap take a closer look at this particular port and see what can be determined.
|
||||
|
||||
```
|
||||
# nmap -sC 192.168.56.102 -p 21
|
||||
|
||||
```
|
||||
[
|
||||
|
||||
][14]
|
||||
|
||||
Nmap – Scan Particular Post on Machine
|
||||
|
||||
With this command, nmap was instructed to run its default script (-sC) on the FTP port (-p 21) on the host. While it may or may not be an issue, nmap did find out that [anonymous FTP login is allowed][13] on this particular server.
|
||||
|
||||
This paired with the earlier knowledge about VSftd having an old vulnerability should raise some concern though. Let’s see if nmap has any scripts that attempt to check for the VSftpd vulnerability.
|
||||
|
||||
```
|
||||
# locate .nse | grep ftp
|
||||
|
||||
```
|
||||
[
|
||||
|
||||
][12]
|
||||
|
||||
Nmap – Scan VSftpd Vulnerability
|
||||
|
||||
Notice that nmap has a NSE script already built for the VSftpd backdoor problem! Let’s try running this script against this host and see what happens but first it may be important to know how to use the script.
|
||||
|
||||
```
|
||||
# nmap --script-help=ftp-vsftd-backdoor.nse
|
||||
|
||||
```
|
||||
[
|
||||
|
||||
][11]
|
||||
|
||||
Learn Nmap NSE Script Usage
|
||||
|
||||
Reading through this description, it is clear that this script can be used to attempt to see if this particular machine is vulnerable to ExploitDB issue identified earlier.
|
||||
|
||||
Let’s run the script and see what happens.
|
||||
|
||||
```
|
||||
# nmap --script=ftp-vsftpd-backdoor.nse 192.168.56.102 -p 21
|
||||
|
||||
```
|
||||
[
|
||||
|
||||
][10]
|
||||
|
||||
Nmap – Scan Host for Vulnerable
|
||||
|
||||
Yikes! Nmap’s script returned some dangerous news. This machine is likely a good candidate for a serious investigation. This doesn’t mean that the machine is compromised and being used for horrible/terrible things but it should bring some concerns to the network/security teams.
|
||||
|
||||
Nmap has the ability to be extremely selective and extremely quite. Most of what has been done so far has attempted to keep nmap’s network traffic moderately quiet however scanning a personally owned network in this fashion can be extremely time consuming.
|
||||
|
||||
Nmap has the ability to do a much more aggressive scan that will often yield much of the same information but in one command instead of several. Let’s take a look at the output of an aggressive scan (Do note – an aggressive scan can set off [intrusion detection/prevention systems][9]!).
|
||||
|
||||
```
|
||||
# nmap -A 192.168.56.102
|
||||
|
||||
```
|
||||
[
|
||||
|
||||
][8]
|
||||
|
||||
Nmap – Complete Network Scan on Host
|
||||
|
||||
Notice this time, with one command, nmap has returned a lot of the information it returned earlier about the open ports, services, and configurations running on this particular machine. Much of this information can be used to help determine [how to protect this machine][7] as well as to evaluate what software may be on a network.
|
||||
|
||||
This was just a short, short list of the many useful things that nmap can be used to find on a host or network segment. It is strongly urged that individuals continue to [experiment with nmap][6] in a controlled manner on a network that is owned by the individual (Do not practice by scanning other entities!).
|
||||
|
||||
There is a official guide on Nmap Network Scanning by author Gordon Lyon, available from Amazon.
|
||||
|
||||
<center style="border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline;">[
|
||||
|
||||
][5]</center>
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: http://www.tecmint.com/nmap-network-security-scanner-in-kali-linux/
|
||||
|
||||
作者：[Rob Turner][a]
|
||||
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:http://www.tecmint.com/author/robturner/
|
||||
[1]:https://sourceforge.net/projects/metasploitable/files/Metasploitable2/
|
||||
[2]:http://www.tecmint.com/install-virtualbox-on-redhat-centos-fedora/
|
||||
[3]:http://www.tecmint.com/kali-linux-installation-guide
|
||||
[4]:http://www.tecmint.com/kali-linux-installation-guide
|
||||
[5]:http://amzn.to/2eFNYrD
|
||||
[6]:http://www.tecmint.com/nmap-command-examples/
|
||||
[7]:http://www.tecmint.com/security-and-hardening-centos-7-guide/
|
||||
[8]:http://www.tecmint.com/wp-content/uploads/2016/11/Nmap-Scan-Network-Host.png
|
||||
[9]:http://www.tecmint.com/protect-apache-using-mod_security-and-mod_evasive-on-rhel-centos-fedora/
|
||||
[10]:http://www.tecmint.com/wp-content/uploads/2016/11/Nmap-Scan-Host-for-Vulnerable.png
|
||||
[11]:http://www.tecmint.com/wp-content/uploads/2016/11/Nmap-Learn-NSE-Script.png
|
||||
[12]:http://www.tecmint.com/wp-content/uploads/2016/11/Nmap-Scan-Service-Vulnerability.png
|
||||
[13]:http://www.tecmint.com/setup-ftp-anonymous-logins-in-linux/
|
||||
[14]:http://www.tecmint.com/wp-content/uploads/2016/11/Nmap-Scan-Particular-Port-on-Host.png
|
||||
[15]:http://www.tecmint.com/commands-to-collect-system-and-hardware-information-in-linux/
|
||||
[16]:http://www.tecmint.com/wp-content/uploads/2016/11/Nmap-Scan-Network-Services-Ports.png
|
||||
[17]:http://www.tecmint.com/find-linux-processes-memory-ram-cpu-usage/
|
||||
[18]:http://www.tecmint.com/find-open-ports-in-linux/
|
||||
[19]:http://www.tecmint.com/find-open-ports-in-linux/
|
||||
[20]:http://www.tecmint.com/wp-content/uploads/2016/11/Nmap-Scan-for-Ports-on-Hosts.png
|
||||
[21]:http://www.tecmint.com/wp-content/uploads/2016/11/Nmap-Ping-All-Network-Live-Hosts.png
|
||||
[22]:http://www.tecmint.com/audit-network-performance-security-and-troubleshooting-in-linux/
|
||||
[23]:http://www.tecmint.com/wp-content/uploads/2016/11/Nmap-Scan-Network.png
|
||||
[24]:http://www.tecmint.com/wp-content/uploads/2016/11/Launch-Terminal-in-Kali-Linux.png
|
||||
[25]:http://www.tecmint.com/terminator-a-linux-terminal-emulator-to-manage-multiple-terminal-windows/
|
||||
[26]:http://www.tecmint.com/wp-content/uploads/2016/11/Start-Desktop-Environment-in-Kali-Linux.png
|
||||
[27]:http://www.tecmint.com/kali-linux-installation-guide
|
||||
[28]:http://insecure.org/fyodor/
|
||||
[29]:http://www.tecmint.com/bcc-best-linux-performance-monitoring-tools/
|
||||
[30]:http://www.tecmint.com/nmap-command-examples/
|
||||
@ -1,119 +0,0 @@
|
||||
ucasFL translating
|
||||
# How to Recover a Deleted File in Linux
|
||||
|
||||
Did this ever happen to you? You realized that you had mistakenly deleted a file – either through the Del key, or using `rm` in the command line.
|
||||
|
||||
In the first case, you can always go to the Trash, [search for the file][6], and restore it to its original location. But what about the second case? As I am sure you probably know, the Linux command line does not send removed files anywhere – it REMOVES them. Bum. They’re gone.
|
||||
|
||||
In this article we will share a tip that may be helpful to prevent this from happening to you, and a tool that you may consider using if at any point you are careless enough to do it anyway.
|
||||
|
||||
### Create an alias to ‘rm -i’
|
||||
|
||||
The `-i` switch, when used with rm (and also other [file-manipulation tools such as cp or mv][5]) causes a prompt to appear before removing a file.
|
||||
|
||||
The same applies to [copying, moving, or renaming a file][4] in a location where one with the same name exists already.
|
||||
|
||||
This prompt gives you a second chance to consider if you actually want to remove the file – if you confirm the prompt, it will be gone. In that case, I’m sorry but this tip will not protect you from your own carelessness.
|
||||
|
||||
To replace rm with an alias to `'rm -i'`, do:
|
||||
|
||||
```
|
||||
alias rm='rm -i'
|
||||
|
||||
```
|
||||
|
||||
The alias command will confirm that rm is now aliased:
|
||||
|
||||
[
|
||||
|
||||
][3]
|
||||
|
||||
Add Alias rm Command
|
||||
|
||||
However, this will only last during the current user session in the current shell. To make the change permanent, you will have to save it to `~/.bashrc` (some distributions may use `~/.profile` instead) as shown below:
|
||||
|
||||
[
|
||||
|
||||
][2]
|
||||
|
||||
Add Alias Permanently in Linux
|
||||
|
||||
In order for the changes in `~/.bashrc` (or `~/.profile`) to take effect immediately, source the file from the current shell:
|
||||
|
||||
```
|
||||
. ~/.bashr
|
||||
|
||||
```
|
||||
[
|
||||
|
||||
][1]
|
||||
|
||||
Active Alias in Linux
|
||||
|
||||
### The forensics tool – Foremost
|
||||
|
||||
Hopefully, you will be careful with your files and will only need to use this tool while recovering a lost file from an external disk or USB drive.
|
||||
|
||||
However, if you realize you accidentally removed a file in your system and are going to panic – don’t. Let’s take a look at foremost, a forensics tool that was designed for this kind of scenarios.
|
||||
|
||||
To install foremost in CentOS/RHEL 7, you will need to enable Repoforge first:
|
||||
|
||||
```
|
||||
# rpm -Uvh http://pkgs.repoforge.org/rpmforge-release/rpmforge-release-0.5.3-1.el7.rf.x86_64.rpm
|
||||
# yum install foremost
|
||||
|
||||
```
|
||||
|
||||
Whereas in Debian and derivatives, just do
|
||||
|
||||
```
|
||||
# aptitude install foremost
|
||||
|
||||
```
|
||||
|
||||
Once the installation has completed, let’s proceed with a simple test. We will begin by removing an image file named `nosdos.jpg` from the /boot/images directory:
|
||||
|
||||
```
|
||||
# cd images
|
||||
# rm nosdos.jpg
|
||||
|
||||
```
|
||||
|
||||
To recover it, use foremost as follows (you’ll need to identify the underlying partition first – `/dev/sda1` is where `/boot` resides in this case):
|
||||
|
||||
```
|
||||
# foremost -t jpg -i /dev/sda1 -o /home/gacanepa/rescued
|
||||
|
||||
```
|
||||
|
||||
where /home/gacanepa/rescued is a directory on a separate disk – keep in mind that recovering files on the same drive where the removed ones were located is not a wise move.
|
||||
|
||||
If, during the recovery, you occupy the same disk sectors where the removed files used to be, it may not be possible to recover anything. Additionally, it is essential to stop all your activities before performing the recovery.
|
||||
|
||||
After foremost has finished executing, the recovered file (if recovery was possible) will be found inside the /home/gacanepa/rescued/jpg directory.
|
||||
|
||||
##### Summary
|
||||
|
||||
In this article we have explained how to avoid removing a file accidentally and how to attempt to recover it if such an undesired event happens. Be warned, however, that foremost can take quite a while to run depending on the size of the partition.
|
||||
|
||||
As always, don’t hesitate to let us know if you have questions or comments. Feel free to drop us a note using the form below.
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: http://www.tecmint.com/recover-deleted-file-in-linux/
|
||||
|
||||
作者：[ Gabriel Cánepa][a]
|
||||
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:http://www.tecmint.com/author/gacanepa/
|
||||
[1]:http://www.tecmint.com/wp-content/uploads/2016/11/Active-Alias-in-Linux.png
|
||||
[2]:http://www.tecmint.com/wp-content/uploads/2016/11/Add-Alias-Permanently-in-Linux.png
|
||||
[3]:http://www.tecmint.com/wp-content/uploads/2016/11/Add-Alias-rm-Command.png
|
||||
[4]:http://www.tecmint.com/rename-multiple-files-in-linux/
|
||||
[5]:http://www.tecmint.com/progress-monitor-check-progress-of-linux-commands/
|
||||
[6]:http://www.tecmint.com/linux-find-command-to-search-multiple-filenames-extensions/
|
||||
@ -0,0 +1,106 @@
|
||||
How To Update Wifi Network Password From Terminal In Arch Linux
|
||||
============================================================
|
||||
|
||||
|
||||
After changing the Wifi Network password in my Router, My Arch Linux test machine lost the Internet connection. So I wanted to update the new password from Terminal because my Arch Linux test box doesn’t have graphical desktop environment. Changing old wifi password to new password is pretty easy in GUI mode. I will simply open the network manager and update the new password to the wifi in few seconds. However, I am not aware of updating the wifi network password from command line in Arch Linux. So, I started to dig into Google and find a perfect solution from the Arch Linux forum. In case you ever been in the same situation, read on. It’s not that difficult.
|
||||
|
||||
|
||||
### Update Wifi Network Password From Terminal
|
||||
|
||||
After changing the password in Router, I ran _wifi-menu_ command to update the new password. But It kept throwing the following error.
|
||||
|
||||
```
|
||||
sudo wifi-menu
|
||||
```
|
||||
|
||||
It displayed the list of available wifi networks.
|
||||
|
||||
[
|
||||
|
||||
][2]
|
||||
|
||||
My wifi network name is Murugs9376. Then, I selected my network and hit OK button. Instead of asking the new password (I thought it was going to ask me if the password has been changed.), It showed the following error.
|
||||
|
||||
```
|
||||
Interface 'wlp9s0' is controlled by netctl-auto
|
||||
WPA association/authentication failed for interface 'wlp9s0'
|
||||
```
|
||||
|
||||
[
|
||||
|
||||
][3]
|
||||
|
||||
I don’t have much experience in Arch based distributions. So I went thorough the Arch linux forum hoping for the solution. Thankfully, someone has posted the same problem and got the workaround from one of the fellow Arch user. Following is the solution to update the wifi network password from Terminal in Arch based distributions.
|
||||
|
||||
The network profiles is stored in the /etc/netctl/ folder. For example, here is my Arch Linux test box wifi network profile details.
|
||||
|
||||
```
|
||||
ls /etc/netctl/
|
||||
|
||||
Sample Output:
|
||||
|
||||
examples ostechnix 'wlp9s0-Chendhan Cell Service' wlp9s0-Pratheesh
|
||||
hooks wlp9s0 wlp9s0-Murugu9376
|
||||
interfaces wlp9s0-AndroidAP wlp9s0-none
|
||||
```
|
||||
|
||||
[
|
||||
|
||||
][4]
|
||||
|
||||
All I need to update the new password is to delete the my wifi network profile (Ex. wlp9s0-Murugs9376) and re-run the _wifi-menu_ command to new password.
|
||||
|
||||
So, first let us delete the wifi profile using command:
|
||||
|
||||
```
|
||||
sudo rm /etc/netctl/wlp9s0-Murugu9376
|
||||
```
|
||||
|
||||
After deleting the profile, run wifi-menu command to update the new password.
|
||||
|
||||
```
|
||||
sudo wifi-menu
|
||||
```
|
||||
|
||||
Select the wifi-network and press ENTER.
|
||||
|
||||
[
|
||||
|
||||
][5]
|
||||
|
||||
Enter a name for the profile.
|
||||
|
||||
[
|
||||
|
||||
][6]
|
||||
|
||||
Finally, Enter the security key to the network profile and hit ENTER key.
|
||||
|
||||
[
|
||||
|
||||
][7]
|
||||
|
||||
That’s it. Now, we have updated the password to the wifi network. As you can see, updating password from Terminal in Arch Linux is no big deal. Anyone could do it in a matter of seconds.
|
||||
|
||||
If you find this guide useful, please share it on your social networks and support us.
|
||||
|
||||
Cheers!
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://www.ostechnix.com/update-wifi-network-password-terminal-arch-linux/
|
||||
|
||||
作者：[ SK][a]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:https://www.ostechnix.com/author/sk/
|
||||
[1]:http://ostechnix.tradepub.com/free/w_pacb38/prgm.cgi?a=1
|
||||
[2]:http://www.ostechnix.com/wp-content/uploads/2016/11/sk@sk_001-1.png
|
||||
[3]:http://www.ostechnix.com/wp-content/uploads/2016/11/sk@sk_002-1.png
|
||||
[4]:http://www.ostechnix.com/wp-content/uploads/2016/11/sk@sk_003-1.png
|
||||
[5]:http://www.ostechnix.com/wp-content/uploads/2016/11/sk@sk_004-1.png
|
||||
[6]:http://www.ostechnix.com/wp-content/uploads/2016/11/sk@sk_005-1.png
|
||||
[7]:http://www.ostechnix.com/wp-content/uploads/2016/11/sk@sk_006-1.png
|
||||
@ -0,0 +1,126 @@
|
||||
翻译中 by zky001
|
||||
How to check if port is in use on Linux or Unix
|
||||
============================================================
|
||||
|
||||
[
|
||||
|
||||
][1]
|
||||
|
||||
How do I determine if a port is in use under Linux or Unix-like system? How can I verify which ports are listening on Linux server?
|
||||
|
||||
It is important you verify which ports are listing on the server’s network interfaces. You need to pay attention to open ports to detect an intrusion. Apart from an intrusion, for troubleshooting purposes, it may be necessary to check if a port is already in use by a different application on your servers. For example, you may install Apache and Nginx server on the same system. So it is necessary to know if Apache or Nginx is using TCP port # 80/443\. This quick tutorial provides steps to use the netstat, nmap and lsof command to check the ports in use and view the application that is utilizing the port.
|
||||
|
||||
### How to check the listening ports and applications on Linux:
|
||||
|
||||
1. Open a terminal application i.e. shell prompt.
|
||||
2. Run any one of the following command:
|
||||
|
||||
```
|
||||
sudo lsof -i -P -n | grep LISTEN
|
||||
sudo netstat -tulpn | grep LISTEN
|
||||
sudo nmap -sTU -O IP-address-Here
|
||||
```
|
||||
|
||||
Let us see commands and its output in details.
|
||||
|
||||
### Option #1: lsof command
|
||||
|
||||
The syntax is:
|
||||
|
||||
```
|
||||
$ sudo lsof -i -P -n
|
||||
$ sudo lsof -i -P -n | grep LISTEN
|
||||
$ doas lsof -i -P -n | grep LISTEN
|
||||
```
|
||||
|
||||
### [OpenBSD] ###
|
||||
|
||||
Sample outputs:
|
||||
|
||||
[
|
||||
|
||||
][2]
|
||||
|
||||
Fig.01: Check the listening ports and applications with lsof command
|
||||
|
||||
Consider the last line from above outputs:
|
||||
|
||||
```
|
||||
sshd 85379 root 3u IPv4 0xffff80000039e000 0t0 TCP 10.86.128.138:22 (LISTEN)
|
||||
```
|
||||
|
||||
- sshd is the name of the application.
|
||||
- 10.86.128.138 is the IP address to which sshd application bind to (LISTEN)
|
||||
- 22 is the TCP port that is being used (LISTEN)
|
||||
- 85379 is the process ID of the sshd process
|
||||
|
||||
### Option #2: netstat command
|
||||
|
||||
You can check the listening ports and applications with netstat as follows.
|
||||
|
||||
### Linux netstat syntax
|
||||
|
||||
```
|
||||
$ netstat -tulpn | grep LISTEN
|
||||
```
|
||||
|
||||
### FreeBSD/MacOS X netstat syntax
|
||||
|
||||
```
|
||||
$ netstat -anp tcp | grep LISTEN
|
||||
$ netstat -anp udp | grep LISTEN
|
||||
```
|
||||
|
||||
### OpenBSD netstat syntax
|
||||
|
||||
````
|
||||
$ netstat -na -f inet | grep LISTEN
|
||||
$ netstat -nat | grep LISTEN
|
||||
```
|
||||
|
||||
### Option #3: nmap command
|
||||
|
||||
The syntax is:
|
||||
|
||||
```
|
||||
$ sudo nmap -sT -O localhost
|
||||
$ sudo nmap -sU -O 192.168.2.13 ##[ list open UDP ports ]##
|
||||
$ sudo nmap -sT -O 192.168.2.13 ##[ list open TCP ports ]##
|
||||
```
|
||||
|
||||
Sample outputs:
|
||||
|
||||
[
|
||||
|
||||
][3]
|
||||
|
||||
Fig.02: Determines which ports are listening for TCP connections using nmap
|
||||
|
||||
You can combine TCP/UDP scan in a single command:
|
||||
|
||||
`$ sudo nmap -sTU -O 192.168.2.13`
|
||||
|
||||
### A note about Windows users
|
||||
|
||||
You can check port usage from Windows operating system using following command:
|
||||
|
||||
```
|
||||
netstat -bano | more
|
||||
netstat -bano | grep LISTENING
|
||||
netstat -bano | findstr /R /C:"[LISTING]"
|
||||
````
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://www.cyberciti.biz/faq/unix-linux-check-if-port-is-in-use-command/
|
||||
|
||||
作者：[ VIVEK GITE][a]
|
||||
译者：[zky001](https://github.com/zky001)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:https://www.cyberciti.biz/faq/unix-linux-check-if-port-is-in-use-command/
|
||||
[1]:https://www.cyberciti.biz/faq/category/linux/
|
||||
[2]:http://www.cyberciti.biz/faq/unix-linux-check-if-port-is-in-use-command/lsof-outputs/
|
||||
[3]:http://www.cyberciti.biz/faq/unix-linux-check-if-port-is-in-use-command/nmap-outputs/
|
||||
@ -0,0 +1,114 @@
|
||||
User Editorial: Steam Machines & SteamOS after a year in the wild
|
||||
====
|
||||
|
||||
|
||||
On this day, last year, [Valve released Steam Machines onto the world][2], after the typical Valve delays. While the state of the Linux desktop regarding gaming has improved, Steam Machines have not taken off as a platform, and SteamOS remains stagnant. What happened with these projects from Valve? Why were they created, why did they fail, and what could have been done to make them succeed?
|
||||
|
||||
**Context**
|
||||
|
||||
In 2012, when Windows 8 released, it included an app store, much like iOS and Android. With the new touch-friendly user interface Microsoft debuted, there was a new set of APIs available called “WinRT,” for creating these immersive touch-friendly applications in the UI language called “Metro.” Applications created with this new API, however, could only be distributed via the Windows Store, with Microsoft taking out a 30% cut, just like the other stores. To Gabe Newell, CEO of Valve, this was unacceptable, and he saw the risks of Microsoft using its position to push the Windows Store and Metro applications to crush Valve, like what they had done to Netscape using Internet Explorer.
|
||||
|
||||
To Valve, the strength of the PC running Windows was it that was an open platform, where anyone could run whatever they want without control over the operating system or hardware vendor. The alternative to these proprietary platforms closing in on third-party application stores like Steam was to push a truly open platform that grants freedoms to change, to everyone – Linux. Linux is just a kernel, but you can easily create an operating system with it and other software like the GNU core utilities and Gnome, such as Ubuntu. While pushing Ubuntu and other Linux distributions would allow Valve a sanctuary platform in case Microsoft or Apple turned hostile, Linux gave them possibilities to create a new platform.
|
||||
|
||||
**Conception**
|
||||
|
||||
Valve seemed to have found an opportunity in the console space, if we can call Steam Machines consoles. To achieve the user interface expectations of a console, being used on a large screen television from afar, Big Picture Mode was created. A core principle of the machines was openness; the software was able to be swapped out for Windows, as an example, and the CAD designs for the controller are available for people’s projects.
|
||||
|
||||
Originally, Valve had planned to create their own box as a “flagship” machine. However, these only shipped as prototypes to testers in 2013\. They would also let other OEMs like Dell create their own Steam Machines as well, and allow a variety of pricing and specification options. A company called “Xi3” showed their small box, small enough to fit into a palm, as a possible candidate to become a premiere Steam Machine, which created more hype around Steam Machines. Ultimately, Valve decided to only go with OEM partners to make and advertise Steam Machines, rather than doing it themselves.
|
||||
|
||||
More “out there” ideas were considered. Biometrics, gaze tracking, and motion controllers were considered for the controller. Of them, the released Steam Controller had a gyroscope, and the HTC Vive controllers had various tracking and motion features that may have been originally intended for the original controller concepts. The controller was also originally intended to be more radical in its approach, with a touchscreen in the middle that had customizable, context-sensitive actions. Ultimately, the launch controller was more conservative, but still had features like the dual trackpads and advanced software that gave it flexibility. Valve had also considered making a version of Steam Machines and SteamOS for smaller hardware like laptops. This ultimately never bore any fruit, though the “Smach Z” handheld could be compared to this.
|
||||
|
||||
In [September 2013][3], Valve had announced Steam Machines and SteamOS, with an expected release in the middle of 2014\. The aforementioned 300 prototype machines were released to testers in December, and in January, 2000 more machines were provided to developers. SteamOS was released for testers experienced with Linux to try out. With the feedback given, Valve had decided to delay the release until November 2015.
|
||||
|
||||
The late launch caused problems with partners; Dell’s Steam Machine was launched a year early running Windows as the Alienware Alpha, with extra software to improve usability with a controller.
|
||||
|
||||
**Launch**
|
||||
|
||||
With the launch, Valve and their OEM partners released their machines, and Valve also released the Steam Controller and the Steam Link. A retail presence was established with GameStop and other brick and mortar stores providing space. Before release, some OEMs pulled out of the launch; Origin PC and Falcon Northwest, two high-end boutique builders. They had claimed performance issues and limitations had made them decide not to ship SteamOS.
|
||||
|
||||
The machines had launched to mixed reviews. The Steam Link was praised and many had considered buying one for their existing PC instead of buying a Steam Machine for the living room. The Steam Controller reception was muddled, due to its rich feature set but high learning curve. The Steam Machines themselves ultimately launched to the muddiest reception, however. Reviewers like LinusTechTips noticed glaring defects with the SteamOS software, including performance issues. Many of the machines were criticized for their high price point and poor value, especially when compared to the option of building a PC from the perspective of a PC gamer, or the price in comparison to other consoles. The use of SteamOS was criticized over compatibility, bugs, and lower performance than Windows. Of the available options, the Alienware Steam Machine was considered to be the most interesting option due to its value relative to other machines and small form factor.
|
||||
|
||||
By using Debian Linux as the base, Valve had many “launch titles” for the platform, as they had a library of pre-existing Linux titles. The initial availability of games was seen as favourable over other consoles. However, many titles originally announced for the platform never came out, or came out much later. Rocket League and Mad Max only came out only recently after the initial announcements a year ago, and titles like The Witcher 3 and Batman: Arkham Knight never came for the platform, despite initial promises from Valve or publishers. In the case of The Witcher 3, the developer, CD Projekt Red, had denied they ever announced a port, despite their game appearing in a list of titles on sale that had or were announced to have Linux and SteamOS support. In addition, many “AAA” titles have not been ported; though this situation continues to improve over time.
|
||||
|
||||
**Neglect**
|
||||
|
||||
With the Steam Machines launched, developers at Valve had moved on to other projects. Of the projects being worked on, virtual reality was seen as the most important, with about a third of employees working on it as of June. Valve had seen virtual reality as something to develop, and Steam as the prime ecosystem for delivering VR. Using HTC to manufacture, they had designed their own virtual reality headset and controllers, and would continue to develop new revisions. However, Linux and Steam Machines had fallen to the wayside with this focus. SteamVR, until recently, did not support Linux (it's still not public yet, but it was shown off at SteamDevDays on Linux), which put into question Valve’s commitments to Steam Machines and Linux as an open platform with a future.
|
||||
|
||||
There has been little development to SteamOS itself. The last major update, SteamOS 2.0 was mostly synchronizing with upstream Debian and required a reinstallation, and continued patches simply continue synchronizing with upstream sources. While Valve has made improvements to projects like Mesa, which have improved performance for many users, it has done little with Steam Machines as a product.
|
||||
|
||||
Many features continue to go undeveloped. Steam’s built in functionality like chat and broadcasting continue to be weak, but this affects all platforms that Steam runs on. More pressingly, services like Netflix, Twitch, and Spotify are not integrated into the interface like most major consoles, but accessing them requires using the browser, which can be slow and clunky, if it even achieves what is wanted, or to bring in software from third-party sources, which requires using the terminal, and the software might not be very usable using a controller –this is a poor UX for what’s considered to be an appliance.
|
||||
|
||||
Valve put little effort into marketing the platform, preferring to leave this to OEMs. However, most OEMs were either boutique builders or makers or barebones builders. Of the OEMs, only Dell was the major player in the PC market, and the only one who pushed Steam Machines with advertisements.
|
||||
|
||||
Sales were not strong. With 500,000 controllers sold 7 months on (stated in June 2016), including those bundled with a Steam Machine. This puts retail Steam Machines, not counting machines people have installed SteamOS on, in the low hundred thousand mark. Compared to the existing PC and console install bases, this is low.
|
||||
|
||||
**Post-mortem thoughts**
|
||||
|
||||
So, with the story of what happened, can we identify why Steam Machines failed, and ways they could succeed in the future?
|
||||
|
||||
_Vision and purpose_
|
||||
|
||||
Steam Machines did not make clear what they were in the market, nor did any advantages particularly stand out. On the PC flank, building PCs had become popular and is a cheaper option with better upgrade and flexibility options. On the console flank, they were outflanked by consoles with low initial investment, despite a possibly higher TCO with game prices, and a far simpler user experience.
|
||||
|
||||
With PCs, flexibility is seen as a core asset, with users being able to use their machines beyond gaming, doing work and other tasks. While Steam Machines were just PCs running SteamOS with no restrictions, the SteamOS software and marketing had solidified their view as consoles to PC gamers, compounded by the price and lower flexibility in hardware with some options. In the living room where these machines could have made sense to PC gamers, the Steam Link offered a way to access content on a PC in another room, and small form factor hardware like NUCs and Mini-ITX motherboards allowed for custom built PCs that are more socially acceptable in living rooms. The SteamOS software was also available to “convert” these PCs into Steam Machines, but people seeking flexibility and compatibility often opted for a Linux or Windows desktop. Recent strides in Windows and desktop Linux have simplified maintenance tasks associated with desktop-experience computers, automating most of it.
|
||||
|
||||
With consoles, simplicity is a virtue. Even as they have expanded in their roles, with media features often a priority, they are still a plug and play experience where compatibility and experience are guaranteed, with a low barrier of entry. Consoles also have long life cycles, ranging from four to seven years, and the fixed hardware during this life cycle allow developers to target and optimize especially for their specifications and features. New mid-life upgrades like “Scorpio” and PlayStation 4 Pro may change the unified experience previously shared by users, but manufactures are requiring games to work on the original model consoles to avoid the most problematic aspects. To keep users attached to the systems, social networks and exclusive games are used. Games also come on discs that can be freely reused and resold, which is a positive for retailers and users. Steam Machines have none of these guarantees; they carry PC complexity and higher initial prices despite a living room friendly exterior.
|
||||
|
||||
_Reconciliation_
|
||||
|
||||
With this, Steam Machines could be seen as a “worst of both worlds” product, carrying the burdens of both kinds of product, without showing clearly as one or the other, or some kind of new product category. There also exist many deficiencies that neither party experiences, like lack of AAA titles that appear on consoles and Windows PCs, and lack of clients for services like Netflix. Despite this, Valve has shown little effort into improving the product or even trying to resolve the seemingly contradictory goals like the mutual distrust of PC and console gaming.
|
||||
|
||||
Some things may make it impossible to reconcile the two concepts into one category or the other, though. Things like graphics settings and mods may make it hard to create a foolproof experience, and the complexity of the underlying system appears from time to time.
|
||||
|
||||
One of the most complex parts is the concept of having a lineup – users need to evaluate not only the costs and specifications of a system, but its value and value relative to other systems. You need some way for the user to know that their hardware can run any given game, either by some automated benchmark system with comparison, or a grading system, though these need to be simple and need to support (almost) every game in the library. In addition, you also need to worry about how these systems and grades will age – what does a “2016 Grade A” machine mean three years from now?
|
||||
|
||||
_Valve, effort, and organization_
|
||||
|
||||
Valve’s organizational structure may be detrimental to creating platforms like Steam Machines, let alone maintaining services like Steam. Their mostly leaderless structure with people supposedly moving their desks to ad-hoc units working on projects that they alone decide to work on can be great for creative endeavours, as well as research and development. It’s said Valve only hires what they consider to be the “cream of the crop,” with very strict standards, tying them to what they deem more "worthy" work. This view may be inaccurate though; as cliques often exist, the word of Gabe Newell is more important than the “leaked” employee handbook lets on, and people hired and then fired as needed, as a form of contractor working on certain aspects.
|
||||
|
||||
However, this leaves projects that aren’t glamorous or interesting, but need persistent and often mundane work, to wither on the vine. Customer support for Valve has been a constant headache, with enraged users felt ignored, and Valve sometimes only acting when legally required to do so, like with the automated refund system that was forced into action by Australian and European legislation, or the Counter-Strike: Global Offensive item gambling site controversy involving the gambling commission of Washington State that’s still ongoing.
|
||||
|
||||
This has affected Steam Machines as a result. With the launch delayed by a year, some partners’ hands were forced, by Dell launching the Alienware Steam Machine a year earlier as the Alienware Alpha – causing the hardware to be outdated on launch. These delays may have also affected game availability as well. The opinions of developers and hardware partners as a result of the delayed and non-monumental launch are not clear. Valve’s platform for virtual reality simply wasn’t available on Linux, and as such, SteamOS, until recently, even as SteamVR was receiving significant developer effort.
|
||||
|
||||
The “long game”
|
||||
|
||||
Valve is seen as playing a “long game” with Steam Machines and SteamOS, though it appears as if there is no roadmap. An example of Valve aiming for the long term is with Steam, from its humble and initially reviled beginnings as a patching platform for their games to the popular distribution and social network it is today. It also helped that Steam was required to play Valve’s games like Half-Life 2 and Counter-Strike 1.6\. However, it doesn’t seem as if Valve is putting in the effort to Steam Machines as they did with Steam before. There is also entrenched competition that Steam in the early days never really dealt with. Their competition includes arguably Valve itself, with Steam on Windows.
|
||||
|
||||
_Gambit_
|
||||
|
||||
With the lack of developments in Steam Machines, one wonders if the platform was a bargaining chip of sorts. Steam Machines had been originally started over Valve’s Linux efforts took fruit because of concerns that Microsoft and Apple would have pushed them out of the market with native app stores, and Steam Machines grew so Valve would have a safe haven in case this happened, and a bargaining chip so Valve can remind the developers of its host platforms of possible independence. When these turned out to be non-threatening, Valve slowed down development. I don’t see this however; Valve has expended a lot of goodwill with hardware partners and developers trying to push this, only to halt it. You could say both Microsoft and Valve called each other’s bluffs – Microsoft with a locked-down Windows 8, and Valve’s capability as an independent player.
|
||||
|
||||
Even then, who is to say developers wouldn’t follow Microsoft with a locked-in platform, if they can offer superior deals to publishers, or better customer relationships? In addition, now Microsoft is pushing Xbox on Windows integration with cross-buy, Xbox Live integration, and Xbox exclusive games on Windows, all while preserving Windows as an open platform – arguably more a threat to Steam.
|
||||
|
||||
Another point you could argue is that all of this with Steam Machines was simply to push Linux adoption with PC gaming, and Steam Machines were simply to make it more palatable to publishers and developers by implying a large push and continued support. However, this made it an awfully expensive gambit, and developers continued to support Linux before and after Steam Machines, and could have backfired with developers pulling out of Linux due to the lack of the Promised Land of SteamOS coming.
|
||||
|
||||
**My opinions on what could have been done**
|
||||
|
||||
I think there’s an interesting product with Steam Machines, and that there is a market for it, but lack of interest and effort, as well as possible confusion in what it should have been has been damaging for it. I see Steam Machines as a way to cut out the complexity of PC gaming of worrying about parts, life cycles, and maintenance; while giving the advantages like cheap games, mods, and an open platform that can be fiddled with if the user desires. However, they need to get core aspects like pricing, marketing, lineup, and software right.
|
||||
|
||||
I think Steam Machines can make compromises on things like upgradability (Though it’s possible to preserve this – but it should be done with attention to user experience.) and choices, to reduce friction. PCs would still exist to these options. The paralysis of choice is a real dilemma, and the sheer amount of poorly valued options available with Steam Machines didn't help. Valve needs a flagship machine to lead Steam Machines. Arguably, the Alienware model was close, but it wasn’t made officially so. There’s good industrial design talent in Valve, and if they focused on their own machine, and with effort put in, it might be worth it. A company like Dell or HTC can manufacture for Valve, bringing their experience in. Defining life cycles and only having one or two specifications updated periodically would help, especially if they worked with developers to establish this is a baseline that should be supported. I’m not sure with OEMs; if Valve is putting their effort behind one machine, they might be made redundant and ultimately only hindering development of the platform.
|
||||
|
||||
Addressing the software issues is essential. The lack of integration with services like Netflix and Twitch that exist fluidly on console and easily put into place on PC, despite living room user interface issues, are holding Steam Machines back. Although Valve has slowly been acquiring movie licenses for distribution on Steam, people will use existing and trusted streaming sources. This needs to be addressed, especially as people use their consoles as parts of their home theatre. Fixing issues with the Steam client and platform are essential, and feature parity with other platforms is a good idea. Performance issues with Linux and its graphics stack are also a problem, but this is slowly improving. Getting ports of games will also be another issue. Game porting shops like Feral Interactive and Aspyr Media help the library, but they need to be contracted by publishers and developers, and they often use wrappers that add overhead. Valve has helped studios directly with porting, such as with Rocket League, but this has rarely happened and when it did, slowly at the typical Valve pace. The monolith of AAA games can’t be ignored either – the situation has improved dramatically, but studios like Bethesda are still reluctant to port, especially with a small user base, lack of support from Valve with Steam Machines even if Linux is doing relatively well, and the lack of extra DRM like Denuvo.
|
||||
|
||||
Valve also needs to put effort into the other bits beyond hardware and software. With one machine, they have an interest and can subsidize the hardware effectively. This would put it into parity with consoles, and possibly cheaper than custom built PCs. Efforts to marketing the product to market segments that would be interested in the machines are essential, whatever they are. (I myself would be interested in the machines. I don’t like the hassle of dealing with PC building or the premium on prebuilt machines, but consoles often lack the games I want to play, and I have an existing library of games on Steam I acquired cheaply.) Retail partners may not be effective, due to their interest in selling and reselling physical copies of games.
|
||||
|
||||
Even with my suggestions towards the platform and product, I’m not sure how effective it would be to help Steam Machines achieve their full potential and do well in the marketplace. Ultimately, learning from not just your own mistakes, but the mistakes of previous entrants like 3DO and Pippin who relied on an open platform or were descended from desktop-experience computing, which are relevant to Valve’s current situation, and the future of Nintendo's Switch, which steps into the realm of possible confusion between values.
|
||||
|
||||
_Note: Clearing up done by liamdawe, all thoughts are from the submitter._
|
||||
|
||||
This article was submitted by a guest, we encourage anyone to [submit their own articles][1].
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://www.gamingonlinux.com/articles/user-editorial-steam-machines-steamos-after-a-year-in-the-wild.8474
|
||||
|
||||
作者：[calvin][a]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:https://www.gamingonlinux.com/profiles/5163
|
||||
[1]:https://www.gamingonlinux.com/submit-article/
|
||||
[2]:https://www.gamingonlinux.com/articles/steam-machines-steam-link-steam-controller-officially-released-steamos-sale.6201
|
||||
[3]:https://www.gamingonlinux.com/articles/valve-announces-steam-machines-you-can-win-one-too.2469
|
||||
@ -0,0 +1,172 @@
|
||||
### [Can Linux containers save IoT from a security meltdown?][28]
|
||||
|
||||
|
||||
In this final IoT series post, Canonical and Resin.io champion Linux container technology as a solution to IoT security and interoperability challenges.
|
||||
|
||||
|
|
||||
|
||||
|
||||
**Artik 7** |
|
||||
|
||||
Despite growing security threats, the Internet of Things hype shows no sign of abating. Feeling the FoMo, companies are busily rearranging their roadmaps for IoT. The transition to IoT runs even deeper and broader than the mobile revolution. Everything gets swallowed in the IoT maw, including smartphones, which are often our windows on the IoT world, and sometimes our hubs or sensor endpoints.
|
||||
|
||||
New IoT focused processors and embedded boards continue to reshape the tech landscape. Since our [Linux and Open Source Hardware for IoT][5] story in September, we’ve seen [Intel Atom E3900][6] “Apollo Lake” SoCs aimed at IoT gateways, as well as [new Samsung Artik modules][7], including a Linux-driven, 64-bit Artik 7 COM for gateways and an RTOS-ready, Cortex-M4 Artik 0\. ARM announced [Cortex-M23 and Cortex-M33][8] cores for IoT endpoints featuring ARMv8-M and TrustZone security.
|
||||
|
||||
Security is a selling point for these products, and for good reason. The Mirai botnet that recently attacked the Dyn service and blacked out much of the U.S. Internet for a day brought Linux-based IoT into the forefront — and not in a good way. Just as IoT devices can be turned to the dark side via DDoS, the devices and their owners can also be the victimized directly by malicious attacks.
|
||||
|
||||
|
|
||||
|
||||
|
||||
**Cortex-M33 and -M23** |
|
||||
|
||||
The Dyn attack reinforced the view that IoT will more confidently move forward in more controlled and protected industrial environments rather than the home. It’s not that consumer [IoT security technology][9] is unavailable, but unless products are designed for security from scratch, as are many of the solutions in our [smart home hub story][10], security adds cost and complexity.
|
||||
|
||||
In this final, future-looking segment of our IoT series, we look at two Linux-based, Docker-oriented container technologies that are being proposed as solutions to IoT security. Containers might also help solve the ongoing issues of development complexity and barriers to interoperability that we explored in our story on [IoT frameworks][11].
|
||||
|
||||
We spoke with Canonical’s Oliver Ries, VP Engineering Ubuntu Client Platform about his company’s Ubuntu Core and its Docker-friendly, container-like Snaps package management technology. We also interviewed Resin.io CEO and co-founder Alexandros Marinos about his company’s new Docker-based ResinOS for IoT.
|
||||
|
||||
**Ubuntu Core Snaps to**
|
||||
|
||||
Canonical’s IoT-oriented [Snappy Ubuntu Core][12] version of Ubuntu is built around a container-like snap package management mechanism, and offers app store support. The snaps technology was recently [released on its own][13] for other Linux distributions. On November 3, Canonical released [Ubuntu Core 16][14], which improves white label app store and update control services.
|
||||
|
||||
<center>
|
||||
[
|
||||
|
||||
][15]
|
||||
**Classic Ubuntu (left) architecture vs. Ubuntu Core 16**
|
||||
(click image to enlarge)
|
||||
</center>
|
||||
|
||||
The snap mechanism offers automatic updates, and helps block unauthorized updates. Using transactional systems management, snaps ensure that updates either deploy as intended or not at all. In Ubuntu Core, security is further strengthened with AppArmor, and the fact that all application files are kept in separate silos, and are read-only.
|
||||
|
||||
|
|
||||
|
||||
|
||||
**LimeSDR** |
|
||||
|
||||
Ubuntu Core, which was part of our recent [survey of open source IoT OSes][16], now runs on Gumstix boards, Erle Robotics drones, Dell Edge Gateways, the [Nextcloud Box][17], LimeSDR, the Mycroft home hub, Intel’s Joule, and SBCs compliant with Linaro’s 96Boards spec. Canonical is also collaborating with the Linaro IoT and Embedded (LITE) Segment Group on its [96Boards IoT Edition][18]Initially, 96Boards IE is focused on Zephyr-driven Cortex-M4 boards like Seeed’s [BLE Carbon][19], but it will expand to gateway boards that can run Ubuntu Core.
|
||||
|
||||
“Ubuntu Core and snaps have relevance from edge to gateway to the cloud,” says Canonical’s Ries. “The ability to run snap packages on any major distribution, including Ubuntu Server and Ubuntu for Cloud, allows us to provide a coherent experience. Snaps can be upgraded in a failsafe manner using transactional updates, which is important in an IoT world moving to continuous updates for security, bug fixes, or new features.”
|
||||
|
||||
|
|
||||
|
||||
|
||||
**Nextcloud Box** |
|
||||
|
||||
Security and reliability are key points of emphasis, says Ries. “Snaps can run completely isolated from one another and from the OS, making it possible for two applications to securely run on a single gateway,” he says. “Snaps are read-only and authenticated, guaranteeing the integrity of the code.”
|
||||
|
||||
Ries also touts the technology for reducing development time. “Snap packages allow a developer to deliver the same binary package to any platform that supports it, thereby cutting down on development and testing costs, deployment time, and update speed,” says Ries. “With snap packages, the developer is in full control of the lifecycle, and can update immediately. Snap packages provide all required dependencies, so developers can choose which components they use.”
|
||||
|
||||
**ResinOS: Docker for IoT**
|
||||
|
||||
Resin.io, which makes the commercial IoT framework of the same name, recently spun off the framework’s Yocto Linux based [ResinOS 2.0][20]” target=”new”>ResinOS 2.0 as an open source project. Whereas Ubuntu Core runs Docker container engines within snap packages, ResinOS runs Docker on the host. The minimalist ResinOS abstracts the complexity of working with Yocto code, enabling developers to quickly deploy Docker containers.
|
||||
|
||||
<center>
|
||||
[
|
||||
|
||||
][21]
|
||||
**ResinOS 2.0 architecture**
|
||||
(click image to enlarge)
|
||||
</center>
|
||||
|
||||
Like the Linux-based CoreOS, ResinOS integrates systemd control services and a networking stack, enabling secure rollouts of updated applications over a heterogeneous network. However, it’s designed to run on resource constrained devices such as ARM hacker boards, whereas CoreOS and other Docker-oriented OSes like the Red Hat based Project Atomic are currently x86 only and prefer a resource-rich server platform. ResinOS can run on 20 Linux devices and counting, including the Raspberry Pi, BeagleBone, and Odroid-C1.
|
||||
|
||||
“We believe that Linux containers are even more important for embedded than for the cloud,” says Resin.io’s Marinos. “In the cloud, containers represent an optimization over previous processes, but in embedded they represent the long-delayed arrival of generic virtualization.”
|
||||
|
||||
|
|
||||
|
||||
|
||||
**BeagleBone
|
||||
Black** |
|
||||
|
||||
When applied to IoT, full enterprise virtual machines have performance issues and restrictions on direct hardware access, says Marinos. Mobile VMs like OSGi and Android’s Dalvik can been used for IoT, but they require Java among other limitations.
|
||||
|
||||
Using Docker may seem natural for enterprise developers, but how do you convince embedded hackers to move to an entirely new paradigm? “Rather than transferring practices from the cloud wholesale, ResinOS is optimized for embedded,” answers Marinos. In addition, he says, containers are better than typical IoT technologies at containing failure. “If there’s a software defect, the host OS can remain functional and even connected. To recover, you can either restart the container or push an update. The ability to update a device without rebooting it further removes failure opportunities.”
|
||||
|
||||
According to Marinos, other benefits accrue from better alignment with the cloud, such as access to a broader set of developers. Containers provide “a uniform paradigm across data center and edge, and a way to easily transfer technology, workflows, infrastructure, and even applications to the edge,” he adds.
|
||||
|
||||
The inherent security benefits in containers are being augmented with other technologies, says Marinos. “As the Docker community pushes to implement signed images and attestation, these naturally transfer to ResinOS,” he says. “Similar benefits accrue when the Linux kernel is hardened to improve container security, or gains the ability to better manage resources consumed by a container.”
|
||||
|
||||
Containers also fit in well with open source IoT frameworks, says Marinos. “Linux containers are easy to use in combination with an almost endless variety of protocols, applications, languages and libraries,” says Marinos. “Resin.io has participated in the AllSeen Alliance, and we have worked with partners who use IoTivity and Thread.”
|
||||
|
||||
**Future IoT: Smarter Gateways and Endpoints**
|
||||
|
||||
Marinos and Canonical’s Ries agree on several future trends in IoT. First, the original conception of IoT, in which MCU-based endpoints communicate directly with the cloud for processing, is quickly being replaced with a fog computing architecture. That calls for more intelligent gateways that do a lot more than aggregate data and translate between ZigBee and WiFi.
|
||||
|
||||
Second, gateways and smart edge devices are increasingly running multiple apps. Third, many of these devices will provide onboard analytics, which we’re seeing in the latest [smart home hubs][22]. Finally, rich media will soon become part of the IoT mix.
|
||||
|
||||
<center>
|
||||
[
|
||||
|
||||
][23] [
|
||||
|
||||
][24]
|
||||
**Some recent IoT gateways: Eurotech’s [ReliaGate 20-26][1] and Advantech’s [UBC-221][2]**
|
||||
(click images to enlarge)
|
||||
</center>
|
||||
|
||||
“Intelligent gateways are taking over a lot of the processing and control functions that were originally envisioned for the cloud,” says Marinos. “Accordingly, we’re seeing an increased push for containerization, so feature- and security-related improvements can be deployed with a cloud-like workflow. The decentralization is driven by factors such as the mobile data crunch, an evolving legal framework, and various physical limitations.”
|
||||
|
||||
Platforms like Ubuntu Core are enabling an “explosion of software becoming available for gateways,” says Canonical’s Ries. “The ability to run multiple applications on a single device is appealing both for users annoyed with the multitude of single-function devices, and for device owners, who can now generate ongoing software revenues.”
|
||||
|
||||
<center>
|
||||
[
|
||||
|
||||
][25] [
|
||||
|
||||
][26]
|
||||
**Two more IoT gateways: [MyOmega MYNXG IC2 Controller (left) and TechNexion’s ][3][LS1021A-IoT Gateway][4]**
|
||||
(click images to enlarge)
|
||||
</center>
|
||||
|
||||
It’s not only gateways — endpoints are getting smarter, too. “Reading a lot of IoT coverage, you get the impression that all endpoints run on microcontrollers,” says Marinos. “But we were surprised by the large amount of Linux endpoints out there like digital signage, drones, and industrial machinery, that perform tasks rather than operate as an intermediary. We call this the shadow IoT.”
|
||||
|
||||
Canonical’s Ries agrees that a single-minded focus on minimalist technology misses out on the emerging IoT landscape. “The notion of ‘lightweight’ is very short lived in an industry that’s developing as fast as IoT,” says Ries. “Today’s premium consumer hardware will be powering endpoints in a matter of months.”
|
||||
|
||||
While much of the IoT world will remain lightweight and “headless,” with sensors like accelerometers and temperature sensors communicating in whisper thin data streams, many of the newer IoT applications use rich media. “Media input/output is simply another type of peripheral,” says Marinos. “There’s always the issue of multiple containers competing for a limited resource, but it’s not much different than with sensor or Bluetooth antenna access.”
|
||||
|
||||
Ries sees a trend of “increasing smartness at the edge” in both industrial and home gateways. “We are seeing a large uptick in AI, machine learning, computer vision, and context awareness,” says Ries. “Why run face detection software in the cloud and incur delays and bandwidth and computing costs, when the same software could run at the edge?”
|
||||
|
||||
As we explored in our [opening story][27] of this IoT series, there are IoT issues related to security such as loss of privacy and the tradeoffs from living in a surveillance culture. There are also questions about the wisdom of relinquishing one’s decisions to AI agents that may be controlled by someone else. These won’t be fully solved by containers, snaps, or any other technology.
|
||||
|
||||
Perhaps we’d be happier if Alexa handled the details of our lives while we sweat the big stuff, and maybe there’s a way to balance privacy and utility. For now, we’re still exploring, and that’s all for the good.
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: http://hackerboards.com/can-linux-containers-save-iot-from-a-security-meltdown/
|
||||
|
||||
作者：[Eric Brown][a]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:http://hackerboards.com/can-linux-containers-save-iot-from-a-security-meltdown/
|
||||
[1]:http://hackerboards.com/atom-based-gateway-taps-new-open-source-iot-cloud-platform/
|
||||
[2]:http://hackerboards.com/compact-iot-gateway-runs-yocto-linux-on-quark/
|
||||
[3]:http://hackerboards.com/wireless-crazed-customizable-iot-gateway-uses-arm-or-x86-coms/
|
||||
[4]:http://hackerboards.com/iot-gateway-runs-linux-on-qoriq-accepts-arduino-shields/
|
||||
[5]:http://hackerboards.com/linux-and-open-source-hardware-for-building-iot-devices/
|
||||
[6]:http://hackerboards.com/intel-launches-14nm-atom-e3900-and-spins-an-automotive-version/
|
||||
[7]:http://hackerboards.com/samsung-adds-first-64-bit-and-cortex-m4-based-artik-modules/
|
||||
[8]:http://hackerboards.com/new-cortex-m-chips-add-armv8-and-trustzone/
|
||||
[9]:http://hackerboards.com/exploring-security-challenges-in-linux-based-iot-devices/
|
||||
[10]:http://hackerboards.com/linux-based-smart-home-hubs-advance-into-ai/
|
||||
[11]:http://hackerboards.com/open-source-projects-for-the-internet-of-things-from-a-to-z/
|
||||
[12]:http://hackerboards.com/lightweight-snappy-ubuntu-core-os-targets-iot/
|
||||
[13]:http://hackerboards.com/canonical-pushes-snap-as-a-universal-linux-package-format/
|
||||
[14]:http://hackerboards.com/ubuntu-core-16-gets-smaller-goes-all-snaps/
|
||||
[15]:http://hackerboards.com/files/canonical_ubuntucore16_diagram.jpg
|
||||
[16]:http://hackerboards.com/open-source-oses-for-the-internet-of-things/
|
||||
[17]:http://hackerboards.com/private-cloud-server-and-iot-gateway-runs-ubuntu-snappy-on-rpi/
|
||||
[18]:http://hackerboards.com/linaro-beams-lite-at-internet-of-things-devices/
|
||||
[19]:http://hackerboards.com/96boards-goes-cortex-m4-with-iot-edition-and-carbon-sbc/
|
||||
[20]:http://hackerboards.com/can-linux-containers-save-iot-from-a-security-meltdown/%3Ca%20href=
|
||||
[21]:http://hackerboards.com/files/resinio_resinos_arch.jpg
|
||||
[22]:http://hackerboards.com/linux-based-smart-home-hubs-advance-into-ai/
|
||||
[23]:http://hackerboards.com/files/eurotech_reliagate2026.jpg
|
||||
[24]:http://hackerboards.com/files/advantech_ubc221.jpg
|
||||
[25]:http://hackerboards.com/files/myomega_mynxg.jpg
|
||||
[26]:http://hackerboards.com/files/technexion_ls1021aiot_front.jpg
|
||||
[27]:http://hackerboards.com/an-open-source-perspective-on-the-internet-of-things-part-1/
|
||||
[28]:http://hackerboards.com/can-linux-containers-save-iot-from-a-security-meltdown/
|
||||
@ -0,0 +1,233 @@
|
||||
Neofetch – Shows Linux System Information with Distribution Logo
|
||||
============================================================
|
||||
|
||||
Neoftech is a cross-platform and easy-to-use [system information command line script][3] that collects your Linux system information and display it on the terminal next to an image, it could be your distributions logo or any ascii art of your choice.
|
||||
|
||||
Neoftech is very similar to [ScreenFetch][4] or [Linux_Logo][5] utilities, but highly customizable and comes with some extra features as discussed below.
|
||||
|
||||
Its main features include: it’s fast, prints a full color image – your distributions logo in ASCII alongside your system information, it’s highly customizable in terms of which, where and when information is printed on the terminal and it can take a screenshot of your desktop when closing the script as enabled by a special flag.
|
||||
|
||||
#### Required Dependencies:
|
||||
|
||||
1. Bash 3.0+ with ncurses support.
|
||||
2. w3m-img (occasionally packaged with w3m) or iTerm2 or Terminology for printing images.
|
||||
3. [imagemagick][1] – for thumbnail creation.
|
||||
4. [Linux terminal emulator][2] should support \033[14t [3] or xdotool or xwininfo + xprop or xwininfo + xdpyinfo .
|
||||
5. On Linux, you need feh, nitrogen or gsettings for wallpaper support.
|
||||
|
||||
Important: You can read more about optional dependencies from the Neofetch Github repository to check if your [Linux terminal emulator][6] actually supports \033[14t or any extra dependencies for the script to work well on your distro.
|
||||
|
||||
### How To Install Neofetch in Linux
|
||||
|
||||
Neofetch can be easily installed from third-party repositories on almost all Linux distributions by following below respective installation instructions as per your distribution.
|
||||
|
||||
#### On Debian
|
||||
|
||||
```
|
||||
$ echo "deb http://dl.bintray.com/dawidd6/neofetch jessie main" | sudo tee -a /etc/apt/sources.list
|
||||
$ curl -L "https://bintray.com/user/downloadSubjectPublicKey?username=bintray" -o Release-neofetch.key && sudo apt-key add Release-neofetch.key && rm Release-neofetch.key
|
||||
$ sudo apt-get update
|
||||
$ sudo apt-get install neofetch
|
||||
```
|
||||
|
||||
#### On Ubuntu and Linux Mint
|
||||
|
||||
```
|
||||
$ sudo add-apt-repository ppa:dawidd0811/neofetch
|
||||
$ sudo apt-get update
|
||||
$ sudo apt-get install neofetch
|
||||
```
|
||||
|
||||
#### On RHEL, CentOS and Fedora
|
||||
|
||||
You need to have dnf-plugins-core installed on your system, or else install it with the command below:
|
||||
|
||||
```
|
||||
$ sudo yum install dnf-plugins-core
|
||||
```
|
||||
|
||||
Enable COPR repository and install neofetch package.
|
||||
|
||||
```
|
||||
$ sudo dnf copr enable konimex/neofetch
|
||||
$ sudo dnf install neofetch
|
||||
```
|
||||
|
||||
#### On Arch Linux
|
||||
|
||||
You can either install neofetch or neofetch-git from the AUR using packer or Yaourt.
|
||||
|
||||
```
|
||||
$ packer -S neofetch
|
||||
$ packer -S neofetch-git
|
||||
OR
|
||||
$ yaourt -S neofetch
|
||||
$ yaourt -S neofetch-git
|
||||
```
|
||||
|
||||
#### On Gentoo
|
||||
|
||||
Install app-misc/neofetch from Gentoo/Funtoo’s official repositories. However, in case you need the git version of the package, you can install =app-misc/neofetch-9999.
|
||||
|
||||
### How To Use Neofetch in Linux
|
||||
|
||||
Once you have installed the package, the general syntax for using it is:
|
||||
|
||||
```
|
||||
$ neofetch
|
||||
```
|
||||
|
||||
Note: If w3m-img or [imagemagick][7] is not installed on your system, [screenfetch][8] will be enabled by default and neofetch will display your [ASCII art logo][9] as in the image below.
|
||||
|
||||
#### Linux Mint Information
|
||||
|
||||
[
|
||||
|
||||
][10]
|
||||
|
||||
Linux Mint System Information
|
||||
|
||||
#### Ubuntu Information
|
||||
|
||||
[
|
||||
|
||||
][11]
|
||||
|
||||
Ubuntu System Information
|
||||
|
||||
If you want to display the default distribution logo as image, you should install w3m-img or imagemagickon your system as follows:
|
||||
|
||||
```
|
||||
$ sudo apt-get install w3m-img [On Debian/Ubuntu/Mint]
|
||||
$ sudo yum install w3m-img [On RHEL/CentOS/Fedora]
|
||||
```
|
||||
|
||||
Then run neofetch again, you will see the default wallpaper of your Linux distributions as the image.
|
||||
|
||||
```
|
||||
$ neofetch
|
||||
```
|
||||
[
|
||||
|
||||
][12]
|
||||
|
||||
Ubuntu System Information with Logo
|
||||
|
||||
After running neofetch for the first time, it will create a configuration file with all options and settings: `$HOME/.config/neofetch/config`.
|
||||
|
||||
This configuration file will enable you through the `printinfo ()` function to alter the system information that you want to print on the terminal. You can type in new lines of information, modify the information lineup, delete certain lines and also tweak the script it using bash code to manage the information to be printed out.
|
||||
|
||||
You can open the configuration file using your favorite editor as follows:
|
||||
|
||||
```
|
||||
$ vi ~/.config/neofetch/config
|
||||
```
|
||||
|
||||
Below is an excerpt of the configuration file on my system showing the `printinfo ()` function.
|
||||
|
||||
Neofetch Configuration File
|
||||
```
|
||||
#!/usr/bin/env bash
|
||||
# vim:fdm=marker
|
||||
#
|
||||
# Neofetch config file
|
||||
# https://github.com/dylanaraps/neofetch
|
||||
|
||||
# Speed up script by not using unicode
|
||||
export LC_ALL=C
|
||||
export LANG=C
|
||||
|
||||
# Info Options {{{
|
||||
|
||||
# Info
|
||||
# See this wiki page for more info:
|
||||
# https://github.com/dylanaraps/neofetch/wiki/Customizing-Info
|
||||
printinfo() {
|
||||
info title
|
||||
info underline
|
||||
|
||||
info "Model" model
|
||||
info "OS" distro
|
||||
info "Kernel" kernel
|
||||
info "Uptime" uptime
|
||||
info "Packages" packages
|
||||
info "Shell" shell
|
||||
info "Resolution" resolution
|
||||
info "DE" de
|
||||
info "WM" wm
|
||||
info "WM Theme" wmtheme
|
||||
info "Theme" theme
|
||||
info "Icons" icons
|
||||
info "Terminal" term
|
||||
info "Terminal Font" termfont
|
||||
info "CPU" cpu
|
||||
info "GPU" gpu
|
||||
info "Memory" memory
|
||||
|
||||
# info "CPU Usage" cpu_usage
|
||||
# info "Disk" disk
|
||||
# info "Battery" battery
|
||||
# info "Font" font
|
||||
# info "Song" song
|
||||
# info "Local IP" localip
|
||||
# info "Public IP" publicip
|
||||
# info "Users" users
|
||||
# info "Birthday" birthday
|
||||
|
||||
info linebreak
|
||||
info cols
|
||||
info linebreak
|
||||
}
|
||||
.....
|
||||
```
|
||||
|
||||
Type the command below to view all flags and their configuration values you can use with neofetch script:
|
||||
|
||||
```
|
||||
$ neofetch --help
|
||||
```
|
||||
|
||||
To launch neofetch with all functions and flags enabled, employ the `--test` flag:
|
||||
|
||||
```
|
||||
$ neofetch --test
|
||||
```
|
||||
|
||||
You can enable the ASCII art logo again using the `--ascii` flag:
|
||||
|
||||
```
|
||||
$ neofetch --ascii
|
||||
```
|
||||
|
||||
In this article, we have covered a simple and highly configuration/customizable command line script that gathers your system information and displays it on the terminal.
|
||||
|
||||
Remember to get in touch with us via the feedback form below to ask any questions or give us your thoughts concerning the neofetch script.
|
||||
|
||||
Last but not least, if you know of any similar scripts out there, do not hesitate to let us know, we will be pleased to hear from you.
|
||||
|
||||
Visit the [neofetch Github repository][13].
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: http://www.tecmint.com/neofetch-shows-linux-system-information-with-logo
|
||||
|
||||
作者：[Aaron Kili ][a]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:http://www.tecmint.com/author/aaronkili/
|
||||
[1]:http://www.tecmint.com/install-imagemagick-in-linux/
|
||||
[2]:http://www.tecmint.com/linux-terminal-emulators/
|
||||
[3]:http://www.tecmint.com/screenfetch-system-information-generator-for-linux/
|
||||
[4]:http://www.tecmint.com/screenfetch-system-information-generator-for-linux/
|
||||
[5]:http://www.tecmint.com/linux_logo-tool-to-print-color-ansi-logos-of-linux/
|
||||
[6]:http://www.tecmint.com/linux-terminal-emulators/
|
||||
[7]:http://www.tecmint.com/install-imagemagick-in-linux/
|
||||
[8]:http://www.tecmint.com/screenfetch-system-information-generator-for-linux/
|
||||
[9]:http://www.tecmint.com/linux_logo-tool-to-print-color-ansi-logos-of-linux/
|
||||
[10]:http://www.tecmint.com/wp-content/uploads/2016/11/Linux-Mint-System-Information.png
|
||||
[11]:http://www.tecmint.com/wp-content/uploads/2016/11/Ubuntu-System-Information.png
|
||||
[12]:http://www.tecmint.com/wp-content/uploads/2016/11/Ubuntu-System-Information-with-Logo.png
|
||||
[13]:https://github.com/dylanaraps/neofetch
|
||||
@ -0,0 +1,231 @@
|
||||
Apache Vs Nginx Vs Node.js And What It Means About The Performance Of WordPress Vs Ghost
|
||||
============================================================
|
||||
|
||||
|
||||
|
||||
Ultimate battle of the giants: can the rising star Node.js prevail against the titans Apache and Nginx?
|
||||
|
||||
|
||||
Just like you, I too have read the various kinds of opinions / facts which are scattered all over the Internet throughout all sorts of sources, some of which I consider reliable, while others, perhaps shady or doubtful.
|
||||
|
||||
Many of the sources I read were quite contradicting, ahm – did someone say StackOverflow?[1][2], others showed a clear yet surprising results[3] thus having a crucial role in pushing me towards running my own tests and experiments.
|
||||
|
||||
At first, I did some thought experiments thinking I may avoid all the hassle of building and running physical tests of my own – I was drowning deep in those before I even knew it.
|
||||
|
||||
Nonetheless, looking backwards on it, it seem that my initial thoughts were quite accurate after all and have been reaffirmed by my tests; a fact which reminds me of what I learned back in school regarding Einstein and his photoelectric effect experiments where he faced a wave–particle duality and initially concluded that the experiments were affected by his state of mind, that is, when he expected the result would be a wave then so it was and vice versa.
|
||||
|
||||
That said, I’m pretty sure my results won’t prove to be a duality anytime in the near future, although my own state of mind probably did had an effect, to some extents, on them.
|
||||
|
||||
### About The Comparison
|
||||
|
||||
One of the sources I read came up with a revolutionary way, in my view, to deal with the natural subjectiveness and personal biases an author may have.
|
||||
|
||||
A way which I decided to embrace as-well, thus I declare the following in advance:
|
||||
|
||||
Developers spend many years honing their craft. Those who reach higher levels usually make their own choice based on a host of factors. It’s subjective; you’ll promote and defend your technology decision.
|
||||
|
||||
That said, the point of this comparison is not to become another “use whatever suits you, buddy” article. I will make recommendations based on my own experience, requirements and biases. You’ll agree with some points and disagree with others; that’s great — your comments will help others make an informed choice.
|
||||
|
||||
And thank you to Craig Buckler of [SitePoint][2] for re-enlightening me regarding the purpose of comparisons – a purpose I tend re-forgetting as I’m trying to please all visitors.
|
||||
|
||||
### About The Tests
|
||||
|
||||
All test were ran locally on an:
|
||||
|
||||
* Intel core i7-2600k machine of 4 cores and 8 threads.
|
||||
* **[Gentoo Linux][1]** is the operating system used to run the tests.
|
||||
|
||||
The tool used for benchmarking: ApacheBench, Version 2.3 <$Revision: 1748469 $>.
|
||||
|
||||
The tests included a series of benchmarks, starting from 1,000 to 10,000 requests and a concurrency of 100 to 1,000 – the results were quite surprising.
|
||||
|
||||
In addition, stress test to measure server function under high load was also issued.
|
||||
|
||||
As for the content, the main focus was about a static file containing a number of Lorem Ipsum verses with headings and an image.
|
||||
|
||||
[
|
||||
|
||||
][3]
|
||||
|
||||
Lorem Ipsum and ApacheBenchmark
|
||||
|
||||
The reason I decided to focus on static files is because they remove all sorts of rendering factors that may have an effect on the tests, such as: the speed of a programming language interpreter, how well is an interpreter integrated with the server, etc…
|
||||
|
||||
Also, based on my own experience, a substantial part of the average page load time is usually being spent on static content such as images for example, therefore in order to see which server could save us the most of that precious time it seem more realistic to focus on that part.
|
||||
|
||||
That aside, I also wanted to test a more real case scenario where I benchmarked each server upon running a dynamic page of different CMSs (more details about that later on).
|
||||
|
||||
### The Servers
|
||||
|
||||
As I’m running Gentoo Linux, you could say that either one of my HTTP servers is starting from an optimized state to begin with, since I built them using only the use-flags I actually needed. I.e there shouldn’t be any unnecessary code or module loading or running in the background while I ran my tests.
|
||||
|
||||
[
|
||||
|
||||
][4]
|
||||
|
||||
Apache vs Nginx vs Node.js use-flags
|
||||
|
||||
### Apache
|
||||
|
||||
`$: curl -i http://localhost/index.html
|
||||
HTTP/1.1 200 OK
|
||||
Date: Sun, 30 Oct 2016 15:35:44 GMT
|
||||
Server: Apache
|
||||
Last-Modified: Sun, 30 Oct 2016 14:13:36 GMT
|
||||
ETag: "2cf2-54015b280046d"
|
||||
Accept-Ranges: bytes
|
||||
Content-Length: 11506
|
||||
Cache-Control: max-age=600
|
||||
Expires: Sun, 30 Oct 2016 15:45:44 GMT
|
||||
Vary: Accept-Encoding
|
||||
Content-Type: text/html`
|
||||
|
||||
Apache was configured with “event mpm”.
|
||||
|
||||
### Nginx
|
||||
|
||||
`$: curl -i http://localhost/index.html
|
||||
HTTP/1.1 200 OK
|
||||
Server: nginx/1.10.1
|
||||
Date: Sun, 30 Oct 2016 14:17:30 GMT
|
||||
Content-Type: text/html
|
||||
Content-Length: 11506
|
||||
Last-Modified: Sun, 30 Oct 2016 14:13:36 GMT
|
||||
Connection: keep-alive
|
||||
Keep-Alive: timeout=20
|
||||
ETag: "58160010-2cf2"
|
||||
Accept-Ranges: bytes`
|
||||
|
||||
Nginx included various tweaks, among them: “sendfile on”, “tcp_nopush on” and “tcp_nodelay on”.
|
||||
|
||||
### Node.js
|
||||
|
||||
`$: curl -i http://127.0.0.1:8080
|
||||
HTTP/1.1 200 OK
|
||||
Content-Length: 11506
|
||||
Etag: 15
|
||||
Last-Modified: Thu, 27 Oct 2016 14:09:58 GMT
|
||||
Content-Type: text/html
|
||||
Date: Sun, 30 Oct 2016 16:39:47 GMT
|
||||
Connection: keep-alive`
|
||||
|
||||
The Node.js server used in the static tests was custom built from scratch, tailor made to be as lightweight and fast as possible – no external modules (outside of Node’s core) were used.
|
||||
|
||||
### The Results
|
||||
|
||||
Click on the images to enlarge:
|
||||
|
||||
[
|
||||
|
||||
][5]
|
||||
|
||||
Apache vs Nginx vs Node: performance under requests load (per 100 concurrent users)
|
||||
|
||||
[
|
||||
|
||||
][6]
|
||||
|
||||
Apache vs Nginx vs Node: performance under concurrent users load (per 1,000 requests)
|
||||
|
||||
### Stress Testing
|
||||
|
||||
[
|
||||
|
||||
][7]
|
||||
|
||||
Apache vs Nginx vs Node: time to complete 100,000 requests with concurrency of 1,000
|
||||
|
||||
### What Can We Learn From The Results?
|
||||
|
||||
Judging by the results above, it appears that Nginx can complete the highest amount of requests in the least amount of time, in other words, **Nginx** is the fastest HTTP server.
|
||||
|
||||
Another thing we can learn, which is quite surprising as a matter of fact, is that Node.js can be faster than Nginx and Apache in some cases, given the right amount of concurrent users and requests.
|
||||
|
||||
To those who wonder, the answer is NO, when the number of requests was raised during the concurrency test then Nginx would return to a leading position.
|
||||
|
||||
Unlike Apache and Nginx, Node.js, especially clustered Node, seem to be indifferent to the number of concurrent users hitting it. As the chart shows, clustered Node keeps a straight line at around 0.1 seconds while both Apache and Nginx suffer a variation of about 0.2 seconds.
|
||||
|
||||
A conclusion that can be drawn based on the above statistics is that the smaller the site is the less it matters which server it uses. However, as the site grows larger audience, the more apparent the impact an HTTP server has.
|
||||
|
||||
At the bottom line, when it comes to the raw speed of each server, as it’s depicted by the stress test, my sense is that the most crucial factor behind the performance is not some special algorithm but what it comes down to is actually the programming language each server is running.
|
||||
|
||||
As both Apache and Nginx are using C language – which is AOT (Ahead Of Time) compiled language, Node.js on the other hand is using JavaScript – which is an interpreted / JIT (Just In Time) compiled language. This means there’s additional work for the Node.js server on its way to execute a program.
|
||||
|
||||
This sense I base not only upon the results above but also upon further results, which you’ll see below, where I got pretty much the same performance parity even when using an optimized Node.js server built with the popular Express framework.
|
||||
|
||||
### The Bigger Picture
|
||||
|
||||
At the end of the day, an HTTP server is quite useless without the content it serves. Therefore when looking to compare web servers, a vital part we must take into account is the content we wish to run on top of it.
|
||||
|
||||
Although other function exists as well, the most widely popular use done with an HTTP server is running a website. Hence, to see the real life implications of each server’s performance I decided to compare WordPress – the most widely used CMS (Content Management System) in the world, with Ghost – a rising star with a gimmick of using JavaScript at its core.
|
||||
|
||||
Will a Ghost web-page based on JavaScript alone be able to outperform a WordPress page running on top of PHP and Apache / Nginx?
|
||||
|
||||
That’s an interesting question since Ghost has the advantage of using a single, coherent tool for its actions – no additional layers needed, whereas WordPress needs to rely on the integration between Apache / Nginx and PHP, an integration which might incur significant performance drawbacks.
|
||||
|
||||
Adding to that, there’s also a significant performance difference between PHP and Node.js in favor of the latter, which I’ll briefly talk about below, things might come out a bit differently than initially seemed.
|
||||
|
||||
### PHP Vs Node.js
|
||||
|
||||
In order to compare WordPress and Ghost we must first consider an essential component which affects both.
|
||||
|
||||
Essentially, WordPress is a PHP based CMS while Ghost is Node.js (JavaScript) based. Unlike PHP, Node.js enjoys the following advantages:
|
||||
|
||||
* Non-blocking I/O
|
||||
* Event driven
|
||||
* Modern, less legacy code encumbered
|
||||
|
||||
Since there are plenty of comparisons out there explaining and demonstrating Node.js raw speed over PHP (including PHP 7) I shall not elaborate further on the subject, Google it, I implore you.
|
||||
|
||||
So, given that Node.js outperforms PHP in general, will it be significant enough to make a Node.js website faster than Apache / Nginx with PHP?
|
||||
|
||||
### WordPress Vs Ghost
|
||||
|
||||
When comparing WordPress to Ghost some would say it’s like comparing apples to oranges and for the most part I’ll agree, as WordPress is a fully fledged CMS while Ghost is basically just a blogging platform at the moment.
|
||||
|
||||
However, the two still share many overlapping areas where both can be used to publish thoughts to the world.
|
||||
|
||||
Given that premise, how can we compare the 2 while one runs on totally different code base than the other, including themes and core features.
|
||||
|
||||
Indeed, a scientific lab-conditioned test would be hard to devise. However, in this comparison I’m interested in a more real life case scenario, where WordPress gets to keep its theme and so does Ghost. Thus, the goal here is to have both platform’s web-pages similar in size as possible and let PHP and Node.js do their magic behind the scenes.
|
||||
|
||||
Since the results were measured against different criteria and most importantly not exact same sizes, it wouldn’t be fair to display them side by side in a chart. Hence a table is used instead:
|
||||
|
||||
[
|
||||
|
||||
][8]
|
||||
|
||||
Node vs Nginx vs Apache running WordPress & Ghost. Top 2 rows are WordPress, bottom 2 are Ghost
|
||||
|
||||
As you can see, despite the fact Ghost (Node.js) is loading a smaller sized page (you’d be surprised how much difference can 1kB make) it still remains slower than both WordPress with Nginx and with Apache.
|
||||
|
||||
Also, does preempting every Node server hit with Nginx proxy that serves as a load balancer actually contributes or detracts from performance?
|
||||
|
||||
Well, according to the table above, if it has any effect at all then it is a detracting one – which is a reasonable outcome as adding another layer should make things slower. However, the numbers above shows it just might be negligible.
|
||||
|
||||
But the most important thing the table above shows us is that even though Node.js is faster than PHP, the role an HTTP server has, may surpass the importance of what type of programming language a certain web platform uses.
|
||||
|
||||
Of course, on the other hand, if the page loaded was a lot more reliant on server-side script serving, then the results would of wind up a bit different, I suspect.
|
||||
|
||||
At the end of it, if a web platform really wants to beat WordPress at its own game, performance-wise that is, the conclusion rising from this comparison is it’ll have to have some sort of customized tool a-la PHP-FPM, that will communicate with JavaScript directly (instead of running it as a server) thus it could fully harness JS power to reach a better performance.
|
||||
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://iwf1.com/apache-vs-nginx-vs-node-js-and-what-it-means-about-the-performance-of-wordpress-vs-ghost/
|
||||
|
||||
作者：[Liron][a]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:https://iwf1.com/tag/linux
|
||||
[1]:http://iwf1.com/5-reasons-use-gentoo-linux/
|
||||
[2]:https://www.sitepoint.com/sitepoint-smackdown-php-vs-node-js/
|
||||
[3]:http://iwf1.com/wordpress/wp-content/uploads/2016/11/Lorem-Ipsum-and-ApacheBenchmark.jpg
|
||||
[4]:http://iwf1.com/wordpress/wp-content/uploads/2016/10/Apache-vs-Nginx-vs-Node.js-use-flags.jpg
|
||||
[5]:http://iwf1.com/wordpress/wp-content/uploads/2016/11/requests.jpg
|
||||
[6]:http://iwf1.com/wordpress/wp-content/uploads/2016/11/concurrency.jpg
|
||||
[7]:http://iwf1.com/wordpress/wp-content/uploads/2016/11/stress.jpg
|
||||
[8]:http://iwf1.com/wordpress/wp-content/uploads/2016/11/Node-vs-Nginx-vs-Apache-comparison-table.jpg
|
||||
@ -0,0 +1,40 @@
|
||||
Introduction to Eclipse Che, a next-generation, web-based IDE
|
||||
============================================================
|
||||
|
||||
|
||||
>Image by : opensource.com
|
||||
|
||||
Correctly installing and configuring an integrated development environment, workspace, and build tools in order to contribute to a project can be a daunting or time consuming task, even for experienced developers. Tyler Jewell, CEO of [Codenvy][1], faced this problem when he was attempting to set up a simple Java project when he was working on getting his coding skills back after dealing with some health issues and having spent time in managerial positions. After multiple days of struggling, Jewell could not get the project to work, but inspiration struck him. He wanted to make it so that "anyone, anytime can contribute to a project with installing software."
|
||||
|
||||
It is this idea that lead to the development of [Eclipse Che][2].
|
||||
|
||||
Eclipse Che is a web-based integrated development environment (IDE) and workspace. Workspaces in Eclipse Che are bundled with an appropriate runtime stack and serve their own IDE, all in one tightly integrated bundle. A project in one of these workspaces has everything it needs to run without the developer having to do anything more than picking the correct stack when creating a workspace.
|
||||
|
||||
The ready-to-go bundled stacks included with Eclipse Che cover most of the modern popular languages. There are stacks for C++, Java, Go, PHP, Python, .NET, Node.js, Ruby on Rails, and Android development. A Stack Library provides even more options and if that is not enough, there is the option to create a custom stack that can provide specialized environments.
|
||||
|
||||
Eclipse Che is a full-featured IDE, not a simple web-based text editor. It is built on Orion and the JDT. Intellisense and debugging are both supported, and version control with both Git and Subversion is integrated. The IDE can even be shared by multiple users for paired programming. With just a web browser, a developer can write and debug their code. However, if a developer would prefer to use a desktop-based IDE, it is possible to connect to the workspace with a SSH connection.
|
||||
|
||||
One of the major technologies underlying Eclipse Che are [Linux containers][3], using Docker. Workspaces are built using Docker and installing a local copy of Eclipse Che requires nothing but Docker and a small script file. The first time `che.sh start` is run, the requisite Docker containers are downloaded and run. If setting up Docker to install Eclipse Che is too much work for you, Codenvy does offer online hosting options. They even provide 4GB workspaces for open source projects for any contributor to the project. Using Codenvy's hosting option or another online hosting method, it is possible to provide a url to potential contributors that will automatically create a workspace complete with a project's code, all with one click.
|
||||
|
||||
Beyond Codenvy, contributors to Eclipse Che include Microsoft, Red Hat, IBM, Samsung, and many others. Several of the contributors are working on customized versions of Eclipse Che for their own specific purposes. For example, Samsung's [Artik IDE][4] for IoT projects. A web-based IDE might turn some people off, but Eclipse Che has a lot to offer, and with so many big names in the industry involved, it is worth checking out.
|
||||
|
||||
* * *
|
||||
|
||||
If you are interested in learning more about Eclipse Che, [CheConf 2016][5] takes place on November 15\. CheConf 2016 is an online conference and registration is free. Sessions start at 11:00 am Eastern time (4:00 pm UTC) and end at 5:30 pm Eastern time (10:30 pm UTC).
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://opensource.com/life/16/11/introduction-eclipse-che
|
||||
|
||||
作者：[Joshua Allen Holm][a]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:https://opensource.com/users/holmja
|
||||
[1]:http://codenvy.com/
|
||||
[2]:http://eclipse.org/che
|
||||
[3]:https://opensource.com/resources/what-are-linux-containers
|
||||
[4]:http://eclipse.org/che/artik
|
||||
[5]:https://eclipse.org/che/checonf/
|
||||
@ -0,0 +1,175 @@
|
||||
Build, Deploy and Manage Custom Apps with IBM Bluemix
|
||||
============================================================
|
||||
|
||||
|
||||
|
||||
|
||||
_IBM’s Bluemix affords developers an opportunity to build, deploy and manage custom apps. Bluemix is built on Cloud Foundry. It supports a number of programming languages as well as OpenWhisk, which allows developers to call any function without the need for resource management._
|
||||
|
||||
Bluemix is an open standards, cloud-based platform implemented by IBM. It has an open architecture which enables organisations to create, develop and manage their applications on the cloud. It is based on Cloud Foundry and hence can be considered as a Platform as a Service (PaaS). With Bluemix, developers need not worry about cloud configurations, but can concentrate on their applications. Cloud configurations will be done automatically by Bluemix.
|
||||
|
||||
Bluemix also provides a dashboard, with which developers can create, manage and view services and applications, while monitoring resource usage also.
|
||||
It supports the following programming languages:
|
||||
|
||||
* Java
|
||||
* Python
|
||||
* Ruby on Rails
|
||||
* PHP
|
||||
* Node.js
|
||||
|
||||
It also supports OpenWhisk (Function as a Service), which is also an IBM product that allows developers to call any function without requiring any resource management.
|
||||
|
||||
|
||||
|
||||
Figure 1: An Overview of IBM Bluemix
|
||||
|
||||
|
||||
|
||||
Figure 2: The IBM Bluemix architecture
|
||||
|
||||
|
||||
|
||||
Figure 3: Creating an organisation in IBM Bluemix
|
||||
|
||||
**How IBM Bluemix works**
|
||||
Bluemix is built on top of IBM’s SoftLayer IaaS (Infrastructure as a Service). It uses Cloud Foundry as an open source PaaS. It starts by pushing code through Cloud Foundry, which plays the role of combining the code and suitable runtime environment based on the programming language in which the application is written. IBM services, third party services or community built services can be used for different functionalities. Secure connectors can be used to connect to on-premise systems and the cloud.
|
||||
|
||||
|
||||
|
||||
Figure 4: Setting up Space in IBM Bluemix
|
||||
|
||||
|
||||
|
||||
Figure 5: The app template
|
||||
|
||||
|
||||
|
||||
Figure 6: IBM Bluemix supported programming languages
|
||||
|
||||
**Creating an app in Bluemix**
|
||||
In this article, we will create a sample ‘Hello World’ application in IBM Bluemix by using the Liberty for Java starter pack, in just a few simple steps.
|
||||
|
||||
1\. Go to [_https://console.ng.bluemix.net/registration/_][2].
|
||||
|
||||
2\. Confirm the Bluemix account.
|
||||
|
||||
3\. Click on the confirmation link in the mail to complete the sign up process.
|
||||
|
||||
4\. Give your email ID and click on _Continue_ to log in.
|
||||
|
||||
5\. Enter the password and click on _Log in._
|
||||
|
||||
6. _Set up_ and _Environment_ share resources in specific regions.
|
||||
|
||||
7\. Create Space to manage access and roll-back in Bluemix. We can map Spaces to development stages such as dev, test, uat, pre-prod and prod.
|
||||
|
||||
|
||||
|
||||
Figure 7: Naming the app
|
||||
|
||||
|
||||
|
||||
Figure 8: Knowing when the app is ready
|
||||
|
||||
|
||||
|
||||
Figure 9: The IBM Bluemix Java App
|
||||
|
||||
8\. Once this initial configuration is completed, click on_ I’m ready_. _Good to Go_!
|
||||
|
||||
9\. Verify the IBM Bluemix dashboard after successfully logging in, specifically sections such as Cloud Foundry Apps where 2GB is available and Virtual Server where 0 instances are available, as of now.
|
||||
|
||||
10\. Click on _Create app_. Choose the template for app creation. In our case, we will go for a Web app.
|
||||
|
||||
11\. How do you get started? Click on Liberty for Java, and then verify the description.
|
||||
|
||||
12\. Click on _Continue_.
|
||||
|
||||
13\. What do you want to name your new app? For this article, let’s use osfy-bluemix-tutorial and click on _Finish_.
|
||||
|
||||
14\. It will take some time to create resources and to host an application on Bluemix.
|
||||
|
||||
15\. In a few minutes, your app will be up and running. Note the URL of the application.
|
||||
|
||||
16\. Visit the application’s URL _http://osfy-bluemix-tutorial.au-syd.mybluemix.net/_. Bingo, our first Java application is up and running on IBM Bluemix.
|
||||
|
||||
17\. To verify the source code, click on _Files_ and navigate to different files and folders in the portal.
|
||||
|
||||
18\. The _Logs_ section provides all the activity logs, starting from the application’s creation.
|
||||
|
||||
19\. The _Environment Variables_ section provides details on all the environment variables of VCAP_Services as well as those that are user defined.
|
||||
|
||||
20\. To verify the application’s consumption of resources, go to the Liberty for Java section.
|
||||
|
||||
21\. The _Overview_ section of each application contains details regarding resources, the application’s health, and activity logs, by default.
|
||||
|
||||
22\. Open Eclipse, go to the Help menu and click on _Eclipse Marketplace_.
|
||||
|
||||
23\. Find _IBM Eclipse tools_ for _Bluemix_ and click on _Install_.
|
||||
|
||||
24\. Confirm the selected features and install them in Eclipse.
|
||||
|
||||
25\. Download the application starter code. Import it into Eclipse by clicking on _File Menu_, select _Import Existing Projects_ into _Workspace_ and start modifying the existing code.
|
||||
|
||||
|
||||
|
||||
Figure 10: The Java app source files
|
||||
|
||||
|
||||
|
||||
Figure 11: The Java app logs
|
||||
|
||||
|
||||
|
||||
Figure 12: Java app — Liberty for Java
|
||||
|
||||
**[
|
||||
][1]Why IBM Bluemix?**
|
||||
Here are some compelling reasons to use IBM Bluemix:
|
||||
|
||||
* Supports multiple languages and platforms
|
||||
* Free trial
|
||||
|
||||
1\. Minimal registration process
|
||||
|
||||
2\. No credit card required
|
||||
|
||||
3\. 30-days trial period – with quotas of 2GB of runtime, 20 services, 500 routes
|
||||
|
||||
4\. Unlimited access to standard support
|
||||
|
||||
5\. No production use limitations
|
||||
|
||||
* Pay only for the use of each runtime and service
|
||||
* Quick set-up – hence faster time to market
|
||||
* Continuous delivery of new features
|
||||
* Secure integration with on-premise resources
|
||||
* Use cases
|
||||
|
||||
1\. Web applications and mobile back-ends
|
||||
|
||||
2\. APIs and on-premise integration
|
||||
|
||||
* DevOps services are available as SaaS on the cloud and support continuous delivery of:
|
||||
|
||||
1\. Web IDE
|
||||
|
||||
2\. SCM
|
||||
|
||||
3\. Agile planning
|
||||
|
||||
4\. Delivery pipeline service
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: http://opensourceforu.com/2016/11/build-deploy-manage-custom-apps-ibm-bluemix/
|
||||
|
||||
作者：[MITESH_SONI][a]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:http://opensourceforu.com/author/mitesh_soni/
|
||||
[1]:http://opensourceforu.com/wp-content/uploads/2016/10/Figure-7-Naming-the-app.jpg
|
||||
[2]:https://console.ng.bluemix.net/registration/
|
||||
@ -0,0 +1,68 @@
|
||||
Is Mozilla Firefox Collecting Your Data Without Your Consent?
|
||||
============================================================
|
||||
|
||||
|
||||
|
||||
|
||||
A geolocation service packaged with Firefox web-browser is running in the background even while the latter is closed.
|
||||
|
||||
We’ve still not fully recovered from the news about the scandalous browser add-on which meant to protect users privacy but instead **[sells their information to third-party companies][1]**, and already we are perhaps in front of another, much bigger in scale, new outrage.
|
||||
|
||||
**MLS** is Mozilla Location Service which lets devices determine their location based on network infrastructure like WiFi access points, cell towers and Bluetooth beacons.
|
||||
|
||||
Pretty much, it is Mozilla’s equivalent to Google Location Service which is the service used when you turn on your GPS on Android devices and opt for ‘High accuracy’ mode.
|
||||
|
||||
Those of you who ever experienced GPS issues will probably know to appreciate how accurate this mode actually is.
|
||||
|
||||
But besides being able to accurately pinpoint your location, another side of it is that the service, through the use of WiFi networks, is able to collect personally identifiable information of both the **users who knowingly contribute to the database** and the **owners of the WiFi devices being scanned**.
|
||||
|
||||
That being said, Mozilla also mentions you can opt out from the service, but can you really?
|
||||
|
||||
### When The Background Becomes Your Privacy Foreground
|
||||
|
||||
Being a [crowdsource][2] project, in order to maintain and grow MLS, Mozilla is in fact dependent of users contributions, thus they’ve developed a number of ways through which users can participate.
|
||||
|
||||
One of these ways, meant to be used by end users is a Android app called Stumbler:
|
||||
|
||||
> “Mozilla Stumbler is an open-source wireless network scanner which collects GPS, cellular and wireless network metadata for our crowd-sourced location database.”[1]
|
||||
|
||||
Yet Stumbler is not only a standalone app but also a service used by Firefox for Android “to contribute data and enhance” MLS.
|
||||
|
||||
The problem with that service lies in the fact it runs in the background without most users are aware of it and **even though you may disable it**.
|
||||
|
||||
According to Mozilla[1], to enable the service you need to open the Settings menu (in Firefox for Android) -> Open the Privacy section -> scroll to the bottom to see the Data Choices, and finally, Check the Mozilla Location Service box.
|
||||
|
||||
[
|
||||
|
||||
][3]
|
||||
|
||||
Mozilla Location Services is unchecked yet Stumbler is on
|
||||
|
||||
In reality, you’ll find that the Stumbler service is **actively running on your device in the background**, meaning it’s practically invisible because it has no interface, even though the MLS box is unchecked and furthermore, even if all the Data Choices check boxes are unchecked and Firefox browser itself is closed.
|
||||
|
||||
Apparently, the only way to stop stumbler is by ending it directly, however to do so, you’ll first need a way to detect it’s running and ultimately, that’s just a temporary solution that only lasts until the device’s next reboot.
|
||||
|
||||
### How To Stay Safer?
|
||||
|
||||
In order to exempt yourself from MLS data collection, there are still a few methods you may practice, in the hope those wouldn’t be disregarded by Mozilla just like the MLS check box in Firefox for Android.
|
||||
|
||||
Make your wireless network hidden or add the string “_nomap” to the end of its name, e.g “myWirelessNetwork” becomes “myWirelessNetwork_nomap”. This should signal Mozilla’s applications that you do not wish to participate in their data collection.
|
||||
|
||||
As for the Stumbler service on Android, due to being a service (as opposed to a process), you’ll probably won’t be able to see it in the list of running processes / recent apps. Thus, either use a dedicated app to close it or enable “Developer Options” and go to “Running services” -> tap on Firefox and finally, stop “stumbler”.
|
||||
|
||||
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://iwf1.com/is-mozilla-firefox-collecting-your-data-without-your-consent/
|
||||
|
||||
作者：[Liron][a]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:https://iwf1.com/is-mozilla-firefox-collecting-your-data-without-your-consent/
|
||||
[1]:https://iwf1.com/shock-this-popular-browser-add-on-sells-your-browsing-history/
|
||||
[2]:https://en.wikipedia.org/wiki/Crowdsourcing
|
||||
[3]:http://iwf1.com/wordpress/wp-content/uploads/2016/11/Mozilla-Location-Services-is-unchecked-yet-Stumler-is-on.jpg
|
||||
@ -0,0 +1,177 @@
|
||||
How to Check Which Apache Modules are Enabled/Loaded in Linux
|
||||
============================================================
|
||||
|
||||
In this guide, we will briefly talk about the Apache web server front-end and how to list or check which Apache modules have been enabled on your server.
|
||||
|
||||
Apache is built, based on the principle of modularity, this way, it enables web server administrators to add different modules to extend its primary functionalities and [enhance apache performance][5] as well.
|
||||
|
||||
Some of the common Apache modules include:
|
||||
|
||||
1. mod_ssl – which offers [HTTPS for Apache][1].
|
||||
2. mod_rewrite – which allows for matching url patterns with regular expressions, and perform a transparent redirect using [.htaccess tricks][2], or apply a HTTP status code response.
|
||||
3. mod_security – which offers you to [protect Apache against Brute Force or DDoS attacks][3].
|
||||
4. mod_status – that allows you to [monitor Apache web server load and page statics][4].
|
||||
|
||||
In Linux, the apachectl or apache2ctl command is used to control Apache HTTP server interface, it is a front-end to Apache.
|
||||
|
||||
You can display the usage information for apache2ctl as below:
|
||||
|
||||
```
|
||||
$ apache2ctl help
|
||||
OR
|
||||
$ apachectl help
|
||||
```
|
||||
apachectl help
|
||||
```
|
||||
Usage: /usr/sbin/httpd [-D name] [-d directory] [-f file]
|
||||
[-C "directive"] [-c "directive"]
|
||||
[-k start|restart|graceful|graceful-stop|stop]
|
||||
[-v] [-V] [-h] [-l] [-L] [-t] [-S]
|
||||
Options:
|
||||
-D name : define a name for use in directives
|
||||
-d directory : specify an alternate initial ServerRoot
|
||||
-f file : specify an alternate ServerConfigFile
|
||||
-C "directive" : process directive before reading config files
|
||||
-c "directive" : process directive after reading config files
|
||||
-e level : show startup errors of level (see LogLevel)
|
||||
-E file : log startup errors to file
|
||||
-v : show version number
|
||||
-V : show compile settings
|
||||
-h : list available command line options (this page)
|
||||
-l : list compiled in modules
|
||||
-L : list available configuration directives
|
||||
-t -D DUMP_VHOSTS : show parsed settings (currently only vhost settings)
|
||||
-S : a synonym for -t -D DUMP_VHOSTS
|
||||
-t -D DUMP_MODULES : show all loaded modules
|
||||
-M : a synonym for -t -D DUMP_MODULES
|
||||
-t : run syntax check for config files
|
||||
```
|
||||
|
||||
apache2ctl can function in two possible modes, a Sys V init mode and pass-through mode. In the SysV init mode, apache2ctl takes simple, one-word commands in the form below:
|
||||
|
||||
```
|
||||
$ apachectl command
|
||||
OR
|
||||
$ apache2ctl command
|
||||
```
|
||||
|
||||
For instance, to start Apache and check its status, run these two commands with root user privileges by employing the [sudo command][6], in case you are a normal user:
|
||||
|
||||
```
|
||||
$ sudo apache2ctl start
|
||||
$ sudo apache2ctl status
|
||||
```
|
||||
Check Apache Status
|
||||
```
|
||||
tecmint@TecMint ~ $ sudo apache2ctl start
|
||||
AH00558: apache2: Could not reliably determine the server's fully qualified domain name, using 127.0.1.1\. Set the 'ServerName' directive globally to suppress this message
|
||||
httpd (pid 1456) already running
|
||||
tecmint@TecMint ~ $ sudo apache2ctl status
|
||||
Apache Server Status for localhost (via 127.0.0.1)
|
||||
|
||||
Server Version: Apache/2.4.18 (Ubuntu)
|
||||
Server MPM: prefork
|
||||
Server Built: 2016-07-14T12:32:26
|
||||
|
||||
-------------------------------------------------------------------------------
|
||||
|
||||
Current Time: Tuesday, 15-Nov-2016 11:47:28 IST
|
||||
Restart Time: Tuesday, 15-Nov-2016 10:21:46 IST
|
||||
Parent Server Config. Generation: 2
|
||||
Parent Server MPM Generation: 1
|
||||
Server uptime: 1 hour 25 minutes 41 seconds
|
||||
Server load: 0.97 0.94 0.77
|
||||
Total accesses: 2 - Total Traffic: 3 kB
|
||||
CPU Usage: u0 s0 cu0 cs0
|
||||
.000389 requests/sec - 0 B/second - 1536 B/request
|
||||
1 requests currently being processed, 4 idle workers
|
||||
|
||||
__W__...........................................................
|
||||
................................................................
|
||||
......................
|
||||
|
||||
Scoreboard Key:
|
||||
"_" Waiting for Connection, "S" Starting up, "R" Reading Request,
|
||||
"W" Sending Reply, "K" Keepalive (read), "D" DNS Lookup,
|
||||
"C" Closing connection, "L" Logging, "G" Gracefully finishing,
|
||||
"I" Idle cleanup of worker, "." Open slot with no current process
|
||||
```
|
||||
|
||||
And when operating in pass-through mode, apache2ctl can take all the Apache arguments in the following syntax:
|
||||
|
||||
```
|
||||
$ apachectl [apache-argument]
|
||||
$ apache2ctl [apache-argument]
|
||||
```
|
||||
|
||||
All the Apache-arguments can be listed as follows:
|
||||
|
||||
```
|
||||
$ apache2 help [On Debian based systems]
|
||||
$ httpd help [On RHEL based systems]
|
||||
```
|
||||
|
||||
#### Check Enabled Apache Modules
|
||||
|
||||
Therefore, in order to check which modules are enabled on your Apache web server, run the applicable command below for your distribution, where `-t -D DUMP_MODULES` is a Apache-argument to show all enabled/loaded modules:
|
||||
|
||||
```
|
||||
--------------- On Debian based systems ---------------
|
||||
$ apache2ctl -t -D DUMP_MODULES
|
||||
OR
|
||||
$ apache2ctl -M
|
||||
```
|
||||
|
||||
```
|
||||
--------------- On RHEL based systems ---------------
|
||||
$ apachectl -t -D DUMP_MODULES
|
||||
OR
|
||||
$ httpd -M
|
||||
$ apache2ctl -M
|
||||
```
|
||||
List Apache Enabled Loaded Modules
|
||||
```
|
||||
[root@tecmint httpd]# apachectl -M
|
||||
Loaded Modules:
|
||||
core_module (static)
|
||||
mpm_prefork_module (static)
|
||||
http_module (static)
|
||||
so_module (static)
|
||||
auth_basic_module (shared)
|
||||
auth_digest_module (shared)
|
||||
authn_file_module (shared)
|
||||
authn_alias_module (shared)
|
||||
authn_anon_module (shared)
|
||||
authn_dbm_module (shared)
|
||||
authn_default_module (shared)
|
||||
authz_host_module (shared)
|
||||
authz_user_module (shared)
|
||||
authz_owner_module (shared)
|
||||
authz_groupfile_module (shared)
|
||||
authz_dbm_module (shared)
|
||||
authz_default_module (shared)
|
||||
ldap_module (shared)
|
||||
authnz_ldap_module (shared)
|
||||
include_module (shared)
|
||||
....
|
||||
```
|
||||
|
||||
That’s all! in this simple tutorial, we explained how to use the Apache front-end tools to list enabled/loaded apache modules. Keep in mind that you can get in touch using the feedback form below to send us your questions or comments concerning this guide.
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: http://www.tecmint.com/check-apache-modules-enabled
|
||||
|
||||
作者：[Aaron Kili][a]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:http://www.tecmint.com/author/aaronkili/
|
||||
[1]:http://www.tecmint.com/install-lets-encrypt-ssl-certificate-to-secure-apache-on-rhel-centos/
|
||||
[2]:http://www.tecmint.com/apache-htaccess-tricks/
|
||||
[3]:http://www.tecmint.com/protect-apache-using-mod_security-and-mod_evasive-on-rhel-centos-fedora/
|
||||
[4]:http://www.tecmint.com/monitor-apache-web-server-load-and-page-statistics/
|
||||
[5]:http://www.tecmint.com/apache-performance-tuning/
|
||||
[6]:http://www.tecmint.com/su-vs-sudo-and-how-to-configure-sudo-in-linux/
|
||||
@ -1,59 +0,0 @@
|
||||
Training vs. hiring to meet the IT needs of today and tomorrow
|
||||
培训还是雇人，来满足当今和未来的 IT 需求
|
||||
================================================================
|
||||
|
||||
|
||||
|
||||
在数字化时代，由于企业需要不断跟上工具和技术更新换代的步伐，对 IT 技能的需求也稳定增长。对于企业来说，寻找和雇佣那些拥有令人垂涎能力的创新人才，是非常不容易的。同时，培训内部员工来使他们接受新的技能和挑战，需要一定的时间。而且，这也往往满足不了需求。
|
||||
|
||||
[Sandy Hill][1] 对多种 IT 学科涉及到的多项技术都很熟悉。她作为 [Pegasystems][2] 项目的 IT 主管，负责的 IT 团队涉及的领域从应用的部署到数据中心的运营。更重要的是，Pegasystems 开发应用来帮助销售，市场，服务以及运行团队简化操作，联系客户。这意味着她需要掌握和利用 IT 内部资源的最佳方法，面对公司客户遇到的 IT 挑战。
|
||||
|
||||
|
||||
|
||||
**企业家项目（TEP）：这些年你是如何调整培训重心的？**
|
||||
|
||||
**Hill**：在过去的几十年中，我们经历了爆炸式的发展，所以现在我们要实现更多的全球化进程。随之而来的培训方面，将确保每个人都在同一起跑线上。
|
||||
|
||||
我们大多的关注点已经转移到培养员工使用新的产品和工具上，这些新产品和工具的实现，能够推动创新，并提高工作效率。例如，我们实现了资产管理系统; 以前我们是没有的。因此我们需要为全部员工做培训，而不是雇佣那些已经知道该产品的人。当我们正在发展的时候，我们也试图保持紧张的预算和稳定的职员总数。所以，我们更愿意在内部培训而不是雇佣新人。
|
||||
|
||||
**TEP：说说培训方法吧，你是怎样帮助你的员工发展他们的技能？**
|
||||
|
||||
**Hill**：我要求每一位员工制定一个技术性的和非技术性的训练目标。这作为他们绩效评估的一部分。他们的技术性目标需要与他们的工作职能相符，非技术行目标则着重发展一项软技能，或是学一些专业领域之外的东西。我每年对职员进行一次评估，看看差距和不足之处，以使团队保持全面发展。
|
||||
|
||||
**TEP：你的训练计划能够在多大程度上减轻招聘和保留职员的问题？**
|
||||
|
||||
**Hill**：使我们的职员对学习新的技术保持兴奋，让他们的技能更好。让职员知道我们重视他们并且让他们在擅长的领域成长和发展，以此激励他们。
|
||||
|
||||
**TEP：你有没有发现哪种培训是最有效的？**
|
||||
|
||||
**HILL**：我们使用几种不同的我们发现是有效的培训方法。当有新的或特殊的项目时，我们尝试加入一套由甲方（不会翻：乙方，卖方？）领导的培训课程，作为项目的一部分。要是这个方法不能实现，我们将进行异地培训。我们也会购买一些在线的培训课程。我也鼓励职员每年参加至少一次会议，以了解行业的动向。
|
||||
|
||||
**TEP：你有没有发现有哪些技能，雇佣新人要比培训现有员工要好？**
|
||||
|
||||
**Hill**：这和项目有关。有一个最近的计划，试图实现 OpenStack，而我们根本没有这方面的专家。所以我们与一家从事这一领域的咨询公司合作。我们利用他们的专业知识帮助我们运行项目，并现场培训我们的内部团队成员。让内部员工学习他们需要的技能，同时还要完成他们们天的工作，这是一项艰巨的任务。
|
||||
|
||||
顾问帮助我们确定我们需要的对某一技术熟练的的员工人数。这使我们能够对员工进行评估，看看是否存在缺口。如果存在人员上的缺口，我们还需要额外的培训或是员工招聘。我们也确实雇佣了一些承包商。另一个选择是让一些全职员工进行为期六至八周的培训，但我们的项目模式不容许这么做。
|
||||
|
||||
**TEP：想一下你最近雇佣的员工，他们的那些技能特别能够吸引到你？**
|
||||
|
||||
**Hill**：在最近的招聘中，我侧重于软技能。除了扎实的技术能力外，他们需要能够在团队中进行有效的沟通和工作，要有说服他人，谈判和解决冲突的能力。
|
||||
|
||||
IT 人一向独来独往。他们一般不是社交最多的人。现在，IT 越来越整合到组织中，它为其他业务部门提供有用的更新报告和状态报告的能力是至关重要的，这也表明 IT 是积极的存在，并将取得成功。
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://enterprisersproject.com/article/2016/6/training-vs-hiring-meet-it-needs-today-and-tomorrow
|
||||
|
||||
作者：[Paul Desmond][a]
|
||||
译者：[Cathon](https://github.com/Cathon)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]: https://enterprisersproject.com/user/paul-desmond
|
||||
[1]: https://enterprisersproject.com/user/sandy-hill
|
||||
[2]: https://www.pega.com/pega-can?&utm_source=google&utm_medium=cpc&utm_campaign=900.US.Evaluate&utm_term=pegasystems&gloc=9009726&utm_content=smAXuLA4U|pcrid|102822102849|pkw|pegasystems|pmt|e|pdv|c|
|
||||
|
||||
|
||||
|
||||
|
||||
@ -1,57 +0,0 @@
|
||||
宽松开源许可证的崛起意味着什么
|
||||
====
|
||||
|
||||
为什么像 GNU GPL 这样的限制性许可证越来越不受青睐。
|
||||
|
||||
“如果你用了任何开源软件， 那么你软件的其他部分也必须开源。” 这是微软 CEO Steve Ballmer 2001 年说的， 尽管他说的不对， 还是引发了人们对自由软件的 FUD （恐惧， 不确定和怀疑）。 大概这才是他的意图。
|
||||
|
||||
对开源软件的这些 FUD 主要与开源许可有关。 现在有许多不同的许可证， 当中有些限制比其他的更严格（也有人称“更具保护性”）。 诸如 GNU 通用公共许可证 （GPL） 这样的限制性许可证使用了 copyleft 的概念。 copyleft 赋予人们自由发布软件副本和修改版的权力， 只要衍生工作给予人们同样的权力。 bash 和 GIMP 等开源项目就是使用了 GPL （v3）。 还有一个 Affero GPL 的许可证， 它为网络上的软件（如网络服务）提供了 copyleft 许可。
|
||||
|
||||
这意味着， 如果你使用了这种许可的代码， 然后加入了你自己的专有代码， 那么在一些情况下， 整个代码， 包括你的代码也就遵从这种限制性开源许可证。 Ballmer 说的大概就是这类的许可证。
|
||||
|
||||
但宽松许可证不同。 比如， 只要保留属性且不要求开发者承担责任， MIT 许可证允许任何人任意使用开源代码， 包括修改和出售。 另一个比较流行的宽松开源许可证， Apache 许可证 2.0 也把专利权从贡献者授予用户。 JQuery, .NET Core 和 Rails 使用了 MIT 许可证， 使用 Apache 许可证 2.0 的软件包括安卓， Apache 和 Swift。
|
||||
|
||||
两种许可证类型最终都是为了让软件更有用。 限制性许可证促进了参与和分享的开源理念， 使每个人从软件中得到最多的利益。 而宽松许可证通过允许人们任意使用软件来确保人们能从软件中得到最多的利益， 即使这意味着他们可以使用代码， 修改它， 据为己有，甚至以专有软件出售，而不做任何回报。
|
||||
|
||||
开源许可证管理公司 Black Duck Software 的数据显示， 去年使用最多的开源许可证是限制性许可证 GPL 2.0, 市占率大约 25%。 宽松许可证 MIT 和 Apache 2.0 次之， 市占率分别为 18% 和 16%， 再后面是 GPL 3.0, 市占率大约 10%。 这样来看， 限制性许可证占 35%， 宽松许可证占 34%， 几乎是平手。
|
||||
|
||||
但这个数据没有显示趋势。 Black Duck 的数据显示， 从 2009 年到 2015 年的六年间， MIT 许可证的市占率上升了 15.7%， Apache 的市占率上升了 12.4%。 在这段时期， GPL v2 和 v3 的市占率惊人地下降了 21.4%。 换言之， 在这段时期里， 大量市占率从限制性许可证移动到宽松许可证。
|
||||
|
||||
这个趋势还在继续。 Black Duck 的[最新数据][1]显示， MIT 现在的市占率为 26%， GPL v2 为 21%， Apache 2 为 16%， GPL v3 为 9%。 即 30% 的限制性许可证和 42% 的宽松许可证－－与前一年的 35% 的限制许可证和 34% 的宽松许可证相比， 发生了重大的转变。 对 GitHub 上使用许可证的[调查研究][2]证实了这种转变。 它显示 MIT 以压倒性的 45% 占有率成为最流行的许可证， 与之相比， GPL v2 只有 13%， Apache 11%。
|
||||
|
||||
|
||||
|
||||
### 引领趋势
|
||||
|
||||
从限制性许可证到宽松许可证，这么大的转变背后是什么呢？ 是公司害怕如果使用了限制性许可证的软件，他们就会像Ballmer说的那样，失去自己私有软件的控制权了吗？ 事实上， 可能就是如此。 比如， Google [禁用了 Affero GPL 软件][3]。
|
||||
|
||||
[Instructional Media + Magic][4] 的主席 Jim Farmer， 是一个教育开源技术的开发者。 他作为很多公司为避开法律问题而不使用限制性许可证。 “问题就在于复杂性。 许可证的复杂性越高， 被人因为某此行为而告上法庭的可能性越高。 高复杂性更可能带来麻烦“， 他说。
|
||||
|
||||
他补充说， 这种对限制性许可证的恐惧正被律师们驱动着， 许多律师建议自己的客户使用 MIT 或 Apache 2.0 许可证的软件， 并明确反对使用 Affero 许可证的软件。
|
||||
|
||||
他说， 这会对软件开发者产生影响， 因为如果公司都避开限制性许可证软件的使用，开发者想要自己的软件被使用， 就更会把新的软件使用宽松许可证。
|
||||
|
||||
但 SalesAgility， 也就是开源 SuiteCRM 的那家公司，的 CEO Greg Soper 认为这种到宽松许可证的转变也由一些开发者驱动。 “看看像 Rocket.Chat 这样的应用。 开发者本可以选择 GPL 2.0 或 Affero 许可证， 但他们选择了宽松许可证，” 他说。 “这样可以给这个应用最大的机会， 因为专有软件厂商可以使用它， 不会伤害到他们的产品， 且不需要把他们的产品也使用开源许可证。 这样如果开发者想要让第三方应用使用他的应用的话， 他有理由选择宽松许可证。”
|
||||
|
||||
Soper 指出， 限制性许可证的设计，就是通过阻止开发者拿了别人的代码，做了修改，但不把结果回报给社区来帮助开源项目。 “ Affero 许可证对我们的产品很重要， 因为如果有人 fork 了，并做得比我们好， 却又不把代码回报回来， 就会杀死我们的产品，” 他说。 “ 对 Rocket.Chat 则不同， 因为如果它使用 Affero， 那么它会污染公司的 IP， 所以公司不会使用它。 不同的许可证有不同的使用案例。”
|
||||
|
||||
曾在 Gnome， 现在是 LibreOffice 的 OpenOffice 上工作的开源开发者 Michael Meeks 同意 Jim Farmer 的，许多公司确实出于对法律的担心，而选择使用宽松许可证的软件的观点。 “copyleft 许可证有风险， 但同样也有巨大的益处。 遗憾的是人们都听从律师， 而律师只是讲风险， 但从不告诉你有些事是安全的。”
|
||||
|
||||
Ballmer 发表他不正确的言论已经 15 年了， 但它产生的 FUD 还是有影响－－即使从限制性许可证到宽松许可证的转变并不是他想要的。
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: http://www.cio.com/article/3120235/open-source-tools/what-the-rise-of-permissive-open-source-licenses-means.html
|
||||
|
||||
作者：[Paul Rubens ][a]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]: http://www.cio.com/author/Paul-Rubens/
|
||||
[1]: https://www.blackducksoftware.com/top-open-source-licenses
|
||||
[2]: https://github.com/blog/1964-open-source-license-usage-on-github-com
|
||||
[3]: http://www.theregister.co.uk/2011/03/31/google_on_open_source_licenses/
|
||||
[4]: http://immagic.com/
|
||||
|
||||
@ -0,0 +1,55 @@
|
||||
# 你会考虑乘坐无人驾驶汽车吗？
|
||||
|
||||
|
||||
|
||||
科技在经历重大进展。最近我们经历的是如苹果手表及各种克隆，FitBit活动智能设备， 谷歌眼镜等可穿戴设备。看起来下一个就是人们研究了很长时间的无人驾驶汽车了。
|
||||
|
||||
这些汽车，有时也叫做自动汽车，自动驾驶汽车，或机器人汽车，确实可以依靠技术自己驾驶。它们能探测周边环境，如障碍物和标志，并使用 GPS 找到自己的路线。但是它们驾驶起来安全吗？我们请教我们的科技作者，“你会考虑乘坐无人驾驶汽车吗？”
|
||||
|
||||
### 我们的观点
|
||||
|
||||
**Derrik** 说他会乘坐无人驾驶汽车，因为 “_技术早就存在，而且很多聪明能干的人研究了很长时间。_” 他承认它们还是有些问题，但他相信很多事故的发生是因为有人的参与。如果不考虑人，他认为乘坐无人驾驶汽车会“_难以置信的安全_。”
|
||||
|
||||
对 **Phil**来说，这些汽车让他“紧张”，但他也承认这是他想象出的，因为他从没乘坐过。他同意 Derrik 这些技术是高度发达的观点，也知道它的原理，但仍然认为“_ 自己新技术接受缓慢，不会购买这类车_” 他甚至坦白说平时很少使用定速巡航。他认为依赖它太多的司机会让他感到不安全。
|
||||
|
||||
|
||||
|
||||
**Robert** 认为“_这个概念确实有点怪，_”但原则上他看不到汽车不向那个方向发展的理由。 他指出飞机已经走了那条路，而且变得更加安全， 他认为事故发生的主因是“_人们过于依赖科技手段，而当科技出现故障时不知所措而导致。_”
|
||||
|
||||
他是一个“焦虑型乘客”， 更喜欢控制整个局面。 对他来说，他的车子在哪里开很重要。如果是以低速在城市中驾驶他感觉还好，但如果是在“宽度不足两车道的弯弯曲曲的英国乡村道路”上，则绝不可以。他和 Phil 都认为英国道路与美国道路大大不同。他建议让别人去做小白鼠， 等到确定安全了再乘坐。
|
||||
|
||||
对 **Mahesh**来说， 他绝对会乘坐无人驾驶汽车，因为他知道这些汽车公司“ 拥有坚实的安全技术，决不会让他们的顾客去冒险。 ” 他承认安全与否还与车辆行驶的道路有关。
|
||||
|
||||
我的观点有些像这些观点的折中。虽然平时我会快速地投入到新科技中，但如果要拿生命去冒险，我不会那么做。我承认这些汽车发展了很久，应该很安全。而且坦率地说，很多司机比无人驾驶汽车危险得多。但和 Robert 一样，我想我会让其他人去做小白鼠，等到它更普遍了再去乘坐。
|
||||
|
||||
|
||||
### 你的观点
|
||||
|
||||
在这个问题上，你的观点是什么呢？ 你会信任新生的科学技术呢，还是乘坐无人驾驶汽车时会紧张到不行？ 你会考虑乘坐无人驾驶汽车吗？ 在下面的评论里加入讨论吧。
|
||||
|
||||
<small style="box-sizing: inherit; font-size: 16px;">图片来自: [Steve Jurvetson][4] 和 [Steve Jurvetson at Wikimedia Commons][3]</small>
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://www.maketecheasier.com/riding-driverless-car/?utm_medium=feed&utm_source=feedpress.me&utm_campaign=Feed%3A+maketecheasier
|
||||
|
||||
作者：[Laura Tucker][a]
|
||||
|
||||
译者：[willcoderwang](https://github.com/willcoderwang)
|
||||
|
||||
校对：[jasminepeng](https://github.com/jasminepeng)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]: https://www.maketecheasier.com/author/lauratucker/
|
||||
[1]:https://www.maketecheasier.com/riding-driverless-car/#comments
|
||||
[2]:https://www.maketecheasier.com/author/lauratucker/
|
||||
[3]:https://commons.m.wikimedia.org/wiki/File:Inside_the_Google_RoboCar_today_with_PlanetLabs.jpg
|
||||
[4]:https://commons.m.wikimedia.org/wiki/File:Jurvetson_Google_driverless_car_trimmed.jpg
|
||||
[5]:https://support.google.com/adsense/troubleshooter/1631343
|
||||
[6]:https://www.maketecheasier.com/best-wordpress-video-plugins/
|
||||
[7]:https://www.maketecheasier.com/hidden-google-games/
|
||||
[8]:mailto:?subject=Would%20You%20Consider%20Riding%20in%20a%20Driverless%20Car?&body=https%3A%2F%2Fwww.maketecheasier.com%2Friding-driverless-car%2F
|
||||
[9]:http://twitter.com/share?url=https%3A%2F%2Fwww.maketecheasier.com%2Friding-driverless-car%2F&text=Would+You+Consider+Riding+in+a+Driverless+Car%3F
|
||||
[10]:http://www.facebook.com/sharer.php?u=https%3A%2F%2Fwww.maketecheasier.com%2Friding-driverless-car%2F
|
||||
[11]:https://www.maketecheasier.com/category/opinion/
|
||||
@ -0,0 +1,86 @@
|
||||
现在Linux运行在99.6%的TOP500超级计算机上
|
||||
============================================================
|
||||
|
||||
[
|
||||
|
||||
][12]
|
||||
|
||||
_简介：虽然Linux在桌面操作系统只有2%的市场占有率，但是对于超级计算机来说，Linux用99%的市场占有率轻松地获取了统治地位_
|
||||
|
||||
Linux运行在超过99%的TOP500超级计算机上，这并不会让人感到惊讶。如果你关注了我们之前2015年的报道[《Linux正运行在超过97%的TOP500超级计算机》][13]，今年Linux表现得更好。
|
||||
|
||||
[#Linux now runs on more than 99% of top 500 #supercomputers in the world][4]
|
||||
|
||||
[CLICK TO TWEET][5]
|
||||
|
||||
这些信息是由独立组织[Top500][4]收集的，每两年他们会公布已知的最快的500台超级计算机的细节。你可以[打开这个网站，用以下条件筛选所需要的信息][15]：国家、使用的操作系统类型、所有者等。别担心，我将会从这份表格中筛选整理出今年几个有趣的事实。
|
||||
|
||||
### Linux运行在500台超级计算机中的498台
|
||||
|
||||
如果要将上面的百分比细化到具体数量的话，500台超级计算机中的498台运行着Linux。剩余的两台超级计算机运行着基于Unix的操作系统。Windows运行在一台超级计算机上，这情况一直持续到去年，今年的列表中没有出现Windows的身影。或许，这些超级计算机没一台能运行Windows 10（一语双关）。
|
||||
|
||||
总结一下今年表单上TOP500超级计算机所运行操作系统情况：
|
||||
|
||||
* Linux: 498
|
||||
* Unix: 2
|
||||
* Windows: 0
|
||||
|
||||
还有一份总结，它清晰展现了每年Linux在TOP500超级计算机的份额的变化情况。
|
||||
|
||||
* 2012年: 94%
|
||||
* [2013][6]年: 95%
|
||||
* [2014][7]年: 97%
|
||||
* [2015][8]年: 97.2%
|
||||
* 2016年: 99.6%
|
||||
* 2017年: ???
|
||||
|
||||
另外，最快的前380台超级计算机运行着Linux，包括中国那台最快的超级计算机。排名第386和第387的超级计算机运行着Unix，它们同样来自中国。
|
||||
|
||||
### 其他关于最快的超级计算机的有趣数据
|
||||
|
||||
[
|
||||
|
||||
][16]
|
||||
|
||||
除去Linux，我在表单中搜寻，找到了几个有趣的数据想跟你分享。
|
||||
|
||||
* 全球最快的超级计算机是[神威太湖一号][9]. 它位于[国家超级计算无锡中心][10]。它有着93PFlops的速度.
|
||||
* 全球第二快的超级计算机是中国的[天河二号][11]，第三的位置则属于美国的Titan。
|
||||
* 在速度前十的超级计算机中，美国占据了5台，日本和中国各有4台，瑞士有1台。
|
||||
* 美国和中国都各有171台超级计算机进入了TOP500的榜单中。
|
||||
* 日本有27台，法国有20台，印度、俄罗斯和沙特阿拉伯各有5台进入了榜单中。
|
||||
|
||||
|
||||
有趣的事实，不是吗？你能点击[这里][18]筛选出属于自己的榜单来获得更多信息。现在我很开心来宣传Linux运行在99%的TOP500超级计算机上，期待下一年能有100%的更好成绩。
|
||||
|
||||
当你在阅读这篇文章时，请在社交平台上分享这篇文章，这是Linux的一个成就，我们引以为豪~:P
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://itsfoss.com/linux-99-percent-top-500-supercomputers
|
||||
|
||||
作者：[Abhishek Prakash ][a]
|
||||
译者：[ypingcn](https://github.com/ypingcn)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]: https://itsfoss.com/author/abhishek/
|
||||
[1]: https://twitter.com/share?original_referer=https%3A%2F%2Fitsfoss.com%2F&source=tweetbutton&text=Linux+Now+Runs+On+99.6%25+Of+Top+500+Supercomputers&url=https%3A%2F%2Fitsfoss.com%2Flinux-99-percent-top-500-supercomputers%2F&via=%40itsfoss
|
||||
[2]: https://www.linkedin.com/cws/share?url=https://itsfoss.com/linux-99-percent-top-500-supercomputers/
|
||||
[3]: http://pinterest.com/pin/create/button/?url=https://itsfoss.com/linux-99-percent-top-500-supercomputers/&description=Linux+Now+Runs+On+99.6%25+Of+Top+500+Supercomputers&media=https://itsfoss.com/wp-content/uploads/2016/11/Linux-King-Supercomputer-world-min.jpg
|
||||
[4]: https://twitter.com/share?text=%23Linux+now+runs+on+more+than+99%25+of+top+500+%23supercomputers+in+the+world&via=itsfoss&related=itsfoss&url=https://itsfoss.com/linux-99-percent-top-500-supercomputers/
|
||||
[5]: https://twitter.com/share?text=%23Linux+now+runs+on+more+than+99%25+of+top+500+%23supercomputers+in+the+world&via=itsfoss&related=itsfoss&url=https://itsfoss.com/linux-99-percent-top-500-supercomputers/
|
||||
[6]: https://itsfoss.com/95-percent-worlds-top-500-supercomputers-run-linux/
|
||||
[7]: https://itsfoss.com/97-percent-worlds-top-500-supercomputers-run-linux/
|
||||
[8]: https://itsfoss.com/linux-runs-97-percent-worlds-top-500-supercomputers/
|
||||
[9]: https://en.wikipedia.org/wiki/Sunway_TaihuLight
|
||||
[10]: https://www.top500.org/site/50623
|
||||
[11]: https://en.wikipedia.org/wiki/Tianhe-2
|
||||
[12]: https://itsfoss.com/wp-content/uploads/2016/11/Linux-King-Supercomputer-world-min.jpg
|
||||
[13]: https://itsfoss.com/linux-runs-97-percent-worlds-top-500-supercomputers/
|
||||
[14]: https://www.top500.org/
|
||||
[15]: https://www.top500.org/statistics/sublist/
|
||||
[16]: https://itsfoss.com/wp-content/uploads/2016/11/fastest-supercomputers.png
|
||||
[17]: https://itsfoss.com/digikam-5-0-released-install-it-in-ubuntu-linux/
|
||||
[18]: https://www.top500.org/statistics/sublist/
|
||||
@ -0,0 +1,68 @@
|
||||
Arch Linux: DIY用户的终结圣地
|
||||
|
||||
|
||||
|
||||
深入研究下Linux系统的新闻史，你会发现其中有一些鲜为人知的Linux发行版，而且关于这些操作系统的新闻报道的数量也十分惊人。
|
||||
|
||||
新发行版中的佼佼者，比如Elementary
|
||||
OS和Solus操作系统因其华丽的界面而被大家所关注，并且，任何搭载MATE桌面环境的操作系统都因其简洁性而被广泛报道。
|
||||
|
||||
感谢像《黑客军团》这样的电视节目，我确信关于Kali Linux系统的报道将会飙升。
|
||||
|
||||
尽管有很多关于Linux系统的报道，然而仍然有一个被广泛使用的Linux发行版几乎被大家完全遗忘了：Arch Linux系统。
|
||||
|
||||
关于Arch的新闻报道很少的原因有很多，其中最主要的原因是它很难安装，而且你还得熟练地在命令行下完成各种配置以使其正常运行。更可怕的是，大多数的用户认为最难的是配置系统，复杂的安装过程令无数的菜鸟们望而怯步。
|
||||
|
||||
这的确很遗憾，在我看来，实际上一旦安装完成后，Arch比我用过的其它Linux发行版更容易得多。
|
||||
|
||||
确实如此，Arch的安装过程很让人蛋疼。有些发行版的安装过程只需要点击“安装”后就可以放手地去干其它事了。Arch相对来说要花费更多的时间和精力去完成硬盘分区，手动挂载，生成fstab文件等。但是从Arch的安装过程中，我们学到很多。它掀开帷幕，让我们弄明白很多背后的东西。事实上，这个帷幕已经彻底消失了，在Arch的世界里，你就是帷幕背后的主宰。
|
||||
|
||||
除了大家所熟知的难安装外，Arch甚至没有自己默认的桌面环境，虽然这有些让人难以理解，但是Arch也因其可定制化而被广泛推崇。你可以自行决定在Arch的基础软件包上安装任何东西。
|
||||
|
||||
![ARCH "DESKTOP" SCREENSHOT LINUX -
|
||||
OBVS VARIES DEPENDING ON USER ](https://regmedia.co.uk/2016/11/01/arch.jpg?x=648&y=364&infer_y=1
|
||||
"ARCH "DESKTOP" SCREENSHOT LINUX - OBVS VARIES DEPENDING ON USER
|
||||
")
|
||||
你可以认为Arch是高度可定制化的，或者说它完全没有定制化。比如，不像Ubuntu系统那样，Arch几乎没有修改过或是定制开发后的软件包。Arch的开发者从始至终都使用上游开发者提供的软件包。对于部分用户来说，这种情况非常棒。比如，你可以使用纯粹的未定制化开发过的GNOME桌面环境。但是，在某些情况下，一些上游开发者未更新过的定制化软件包可能存在很多的缺陷。
|
||||
|
||||
由于Arch缺乏一些默认的应用程序和桌面系统，这完全不利于用户管理自己的桌面环境。我曾经使用最小化安装配置Openbox，tint2和dmenu桌面管理工具，但是安装后的效果却跟我很失望。因此，我更倾向于使用最新版的GNOME桌面系统。在使用Arch的过程中，我们会同时安装一个桌面环境，但是这给我们的体验是完全不一样的。对于任何发行版来说，这种做法是正确的，但是大多数的Linux系统都至少会使用一个默认的桌面环境。
|
||||
|
||||
然而Arch还是有很多共性的元素一起构成这个基本系统。比如说，我使用Arch系统的主要原因是因为它是一个滚动更新的发行版。这意味着两件事情。首先，Arch使用最新的稳定版内核。这就意味着我可以在Arch系统里完成在其它Linux发行版中很难完成的测试。滚动版最大的一个好处就是所有可用的软件更新包会被即时发布出来。这不只是说明软件包更新速度快，而且也没有太多的系统升级包会被拆分。
|
||||
|
||||
由于Arch是一个滚动更新的发行版，因此很多用户认为它是不稳定的。但是在我使用了9个多月之后，我并不赞同这种观点。
|
||||
|
||||
我在每一次升级系统的过程中，从未损坏过任何软件。有一次升级系统之后我不得不回滚，因为系统启动分区/boot无法挂载成功，但是后来我发现那完全是自己操作上的失误。一些基本的系统缺陷（比如我关于戴尔XPS笔记本触摸板相关的回归测试方面的问题）已经被修复，并且可用的软件包更新速度要比其它非滚动发行版快得多。总的来说，我认为Arch滚动更新的发布模式比其它我在用的发行版要稳定得多。唯一一点我要强调的是查阅维基上的资料，多关注你要更新的内容。
|
||||
|
||||
你必须要小心你正在做的操作，因为Arch也不是任你肆意胡来的。盲目的更新Arch系统是极其危险的。但是任何一个发行版的更新都有风险。在你别无选择的时候，你得根据实际情况，三思而后行。
|
||||
|
||||
Arch的哲学理念是我支持它的另外一个最主要的原因。我认为Arch最吸引用户的一点就是：Arch面向的是专业的Linux用户，或者是有“自己动手”的态度，并愿意查资料解决问题的任何人。
|
||||
|
||||
随着Linux逐渐成为主流的操作系统，开发者们更需要顺利地渡过每一个艰难的技术领域。那些晦涩难懂的专有软件方面的经验恰恰能反映出用户高深的技术能力。
|
||||
|
||||
尽管在这个时代听起来有些怪怪的，但是事实上我们大多数的用户更愿意自己动手装配一些东西。在这种情形下，Arch将会是Linux DIY用户的终结圣地。
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
via: http://www.theregister.co.uk/2016/11/02/arch_linux_taster/
|
||||
|
||||
作者：[Scott
|
||||
Gilbertson][a]
|
||||
|
||||
译者：[rusking](https://github.com/rusking)
|
||||
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由
|
||||
[LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:http://www.theregister.co.uk/Author/1785
|
||||
|
||||
[1]:https://wiki.archlinux.org/index.php/Arch_Linux
|
||||
|
||||
[2]:http://www.theregister.co.uk/Author/1785
|
||||
|
||||
[3]:https://www.linkedin.com/shareArticle?mini=true&url=http://www.theregister.co.uk/2016/11/02/arch_linux_taster/&title=Arch%20Linux%3A%20In%20a%20world%20of%20polish%2C%20DIY%20never%20felt%20so%20good&summary=Last%20refuge%20for%20purists
|
||||
|
||||
[4]:http://twitter.com/share?text=Arch%20Linux%3A%20In%20a%20world%20of%20polish%2C%20DIY%20never%20felt%20so%20good&url=http://www.theregister.co.uk/2016/11/02/arch_linux_taster/&via=theregister
|
||||
|
||||
[5]:http://www.reddit.com/submit?url=http://www.theregister.co.uk/2016/11/02/arch_linux_taster/&title=Arch%20Linux%3A%20In%20a%20world%20of%20polish%2C%20DIY%20never%20felt%20so%20good
|
||||
@ -1,101 +0,0 @@
|
||||
我成为一名软件工程师的原因和经历
|
||||
==========================================
|
||||
|
||||
|
||||
|
||||
1989 年乌干达首都，坎帕拉。
|
||||
|
||||
赞美我的父母，他们机智的把我送到叔叔的办公室，去学着用电脑，而非将我留在家里添麻烦。几日后，我和另外六、七个小孩，还有一台放置在与讲台相垂直课桌子上的崭新电脑，一起置身于 21 层楼高的狭小房间中。很明显我们还不够格去碰那家伙。在长达三周无趣的 DOS 命令学习后，终于迎来了这美妙的时光。终于轮到我来输 **copy doc.txt d:** 了。
|
||||
|
||||
那奇怪的声音其实是将一个简单文件写入五英寸软盘的声音，但听起来却像音乐般美妙。那段时间，这块软盘简直成为了我的至宝。我把所有我可以拷贝的东西都放在上面了。然而，1989 年的乌干达，人们的生活十分正经，相较而言捣鼓电脑，拷贝文件还有格式化磁盘就称不上正经。我不得不专注于自己的学业，这让我离开了计算机科学走入了建筑工程学。
|
||||
|
||||
在这些年里，我和同龄人一样，干过很多份工作也学到了许多技能。我教过幼儿园的小朋友，也教过大人如何使用软件，在服装店工作过，还在教堂中担任过付费招待。在我获取堪萨斯大学的学位时，我正在技术高管的手下做技术助理，其实也就听上去比较洋气，也就是搞搞学生数据库而已。
|
||||
|
||||
当我 2007 年毕业时，这些技术已经变得不可或缺。建筑工程学的方方面面都与计算机科学深深的交织在一起，所以我们也都在不经意间也都学了些简单的编程知识。我对于这方面一直很着迷。但由于我不得不成为一位正经的工程师，所以我发展了一项私人爱好：写科幻小说。
|
||||
|
||||
在我的故事中，我以我笔下的女英雄的形式存在。她们都是编程能力出众的科学家，总是在冒险的途中用自己的技术发明战胜那些渣渣们，有时发明要在战斗中进行。我想出的这些“新技术”，一般基于真实世界中的发明。也有些是从买来的科幻小说中读到的。这就意味着我需要了解这些技术的原理，而且我的研究使我有意无意的关注了许多有趣的 subreddit 和电子杂志
|
||||
|
||||
### 开源：巨大的宝库
|
||||
|
||||
在我的经历中，那几周花在 DOS 命令上的时间仍然记忆犹新，在一些偏门的项目上耗费心血，并占据了宝贵的学习时间。Geocities 一向所有 Yahoo! 用户开放，我就创建了一个网站，用于发布一些由我用小型数码相机拍摄的个人图片。这个网站是我随性而为的，用来帮助家人和朋友，解决一些他们所遇到的电脑问题。同时也为教堂搭建了一个图书馆数据库。
|
||||
|
||||
这意味着，我需要一直研究并尝试获取更多的信息，使它们变得更棒。上帝保佑，让互联网和开源砸在了我的面前。然后，30 天试用和 license 限制对我而言就变成了过去式。我可以完全不受这些限制，持续的使用 GIMP、Inkscape 和 OpenOffice。
|
||||
|
||||
### 是时候正经了
|
||||
|
||||
我很幸运，有商业伙伴看出了我故事中的奇妙。她也是个想象力丰富的人，对更高效、更便捷的互联这个世界，充满了各种美好的想法。我们根据我们以往成功道路中经历的痛点制定了解决方案，但执行却成了一个问题。我们都缺乏那种将产品带入生活的能力，每当我们试图将想法带到投资人面前时，都表现的尤为突出。
|
||||
|
||||
我们需要学习编程。所以在 2015 年的夏末，我们踏上了征途，来到了 Holberton 学校的阶前。那是一所座落于旧金山由社区推进，基于项目教学的学校。
|
||||
|
||||
我的商业伙伴一天早上找到我，并开始了一段充满她方式的对话，每当她有疯狂想法想要拉我入伙时。
|
||||
|
||||
**Zee**: Gloria，我想和你说点事，在拒绝前能先听我说完吗？
|
||||
|
||||
**Me**: 不行。
|
||||
|
||||
**Zee**: 我们想要申请一所学校的全栈工程师。
|
||||
|
||||
**Me**: 什么？
|
||||
|
||||
**Zee**: 就是这，看！就是这所学校，我们要申请这所学校学习编程。
|
||||
|
||||
**Me**: 我不明白。我们不是正在网上学 Python 和…
|
||||
|
||||
**Zee**: 这不一样。相信我。
|
||||
|
||||
**Me**: 那…
|
||||
|
||||
**Zee**: 还不相信吗？
|
||||
|
||||
**Me**: 好吧…我看看。
|
||||
|
||||
### 抛开偏见
|
||||
|
||||
我看到的和我们在网上听说的几乎差不多。这简直太棒了，以至于让人觉得不太真实，但我们还是决定尝试一下，双脚起跳，看看结果如何。
|
||||
|
||||
要成为学生，我们需要经历四个步骤，仅仅是针对才能和态度，无关学历和编程经历的筛选。筛选便是课程的开始，通过它我们开始学习与合作。
|
||||
|
||||
根据我和我合作伙伴的经验，相比 Holberton 学校的申请流程，其他的申请流程实在是太无聊了。就像场游戏。如果你完成了一项挑战，你就能通往下一关，在那里有别的有趣的挑战正等着你。我们创建了 Twitter 账号，在 Medium 上写博客，为了创建网站而学习 HTML 和 CSS， 打造了一个充满活力的社区，虽然在此之前我们并不知晓有谁会来。
|
||||
|
||||
在线社区最吸引人的就是我们使用电脑的经验是多种多样的，而我们的背景和性别并非创始人（我们私下里称他为“The Trinity（三位一体）”）做出选择的因素。大家只是喜欢聚在一块交流。我们都是通过学习编程来提升自己计算机技术的聪明人。
|
||||
|
||||
相较于其他的的申请流程，我们不需要泄露很多的身份信息。就像我的商业伙伴，她的名字里看不出她的性别和种族。直到最后一个步骤，在视频聊天的时候， The Trinity 才知道她是一位有色人种女性。迄今为止，促使她达到这个程度的只是她的热情和才华。肤色和性别，并没有妨碍或者帮助到她。还有比这更酷的吗？
|
||||
|
||||
那个我们获得录取通知书的晚上，我们知道我们的命运已经改变，我们获得了原先梦寐以求的生活。2016 年 1 月 22 日，我们来到北至巴特瑞大街 98 号，去见我们的小伙伴 [Hippokampoiers][2]，这是我们的初次见面。很明显，在见面之前，“The Trinity”就已经开始做一些令人激动的事了。他们已经聚集了一批形形色色的人，他们都专注于成为全栈工程师，并为之乐此不疲。
|
||||
|
||||
这所大学有种与众不同的体验。感觉每天都是向编程的一次竭力的冲锋。我们着手的工程，并不会有很多指导，我们需要使用一切我们可以使用的资源找出解决方案。[Holberton 学校][1] 的办学宗旨便是向学员提供，相较于我们已知而言，更为多样的信息渠道。MOOCs（大型开放式课程）、教程、可用的开源软件和项目，以及线上社区层出不穷，将我们完成项目所需要的知识全都衔接了起来。加之宝贵的导师团队来指导我们制定解决方案，这所学校变得并不仅仅是一所学校；我们已经成为了求学者的社区。任何对软件工程感兴趣并对这种学习方法感兴趣的人，我都十分推荐这所学校。下次开课在 2016 年 10 月，并且会接受新的申请。虽然会让人有些悲喜交加，但是那真的很值得。
|
||||
|
||||
### 开源问题
|
||||
|
||||
我最早使用的开源系统是 [Fedora][3]，一个 [Red Hat][4] 赞助的项目。在与 IRC 中一名成员一番惊慌失措的交流后，她推荐了这款免费的系统。 虽然在此之前，我还未独自安装过操作系统，但是这激起了我对开源的兴趣和日常使用计算机时对开源软件的依赖性。我们提倡为开源贡献代码，创造并使用开源的项目。我们的项目就在 Github 上，任何人都可以使用或是向它贡献出自己的力量。我们也会使用或以自己的方式为一些既存的开源项目做出贡献。在学校里，我们使用的大部分工具是开源的，例如 Fedora、[Vagrant][5]、[VirtualBox][6]、[GCC][7] 和 [Discourse][8]，仅举几例。
|
||||
|
||||
重回软件工程师之路以后，我始终憧憬着有这样一个时刻——能为开源社区做出一份贡献，能与他人分享我所掌握的知识。
|
||||
|
||||
### Diversity Matters
|
||||
|
||||
站在教室里，在着 29 双明亮的眼睛关注下交流心得，真是令人陶醉。学员中有 40% 是女性，有 44% 的有色人种。当你是一位有色人种且为女性，并身处于这个以缺乏多样而著名的领域时，这些数字就变得非常重要了。那是高科技圣地麦加上的绿洲。我知道我做到了。
|
||||
|
||||
想要成为一个全栈的工程师是十分困难的，你甚至很难了解这意味着什么。这是一条充满挑战的路途，道路四周布满了对收获的未知。科技推动着未来飞速发展，而你也是美好未来很重要的一部分。虽然媒体在持续的关注解决科技公司的多样化的问题，但是如果能认清自己，了解自己，知道自己为什么想成为一名全栈工程师，这样你便能觅得一处生根发芽。
|
||||
|
||||
不过可能最重要的是，提醒人们女性在计算机的发展史上扮演着多么重要的角色，以帮助更多的女性回归到科技界，并使她们充满期待，而非对自己的性别与能力感到犹豫。她们的才能将会描绘出不仅仅是科技的未来，而是整个世界的未来。
|
||||
|
||||
|
||||
------------------------------------------------------------------------------
|
||||
|
||||
via: https://opensource.com/life/16/4/my-open-source-story-gloria-bwandungi
|
||||
|
||||
作者：[Gloria Bwandungi][a]
|
||||
译者：[martin2011qi](https://github.com/martin2011qi)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创翻译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:https://opensource.com/users/nappybrain
|
||||
[1]: https://www.holbertonschool.com/
|
||||
[2]: https://twitter.com/hippokampoiers
|
||||
[3]: https://en.wikipedia.org/wiki/Fedora_(operating_system)
|
||||
[4]: https://www.redhat.com/
|
||||
[5]: https://www.vagrantup.com/
|
||||
[6]: https://www.virtualbox.org/
|
||||
[7]: https://gcc.gnu.org/
|
||||
[8]: https://www.discourse.org/
|
||||
@ -1,51 +1,52 @@
|
||||
# aria2 (Command Line Downloader) command examples
|
||||
# aria2 （命令行下载器）命令行实例
|
||||
|
||||
[aria2][4] is a Free, open source, lightweight multi-protocol & multi-source command-line download utility. It supports HTTP/HTTPS, FTP, SFTP, BitTorrent and Metalink. aria2 can be manipulated via built-in JSON-RPC and XML-RPC interfaces. aria2 automatically validates chunks of data while downloading a file. It can download a file from multiple sources/protocols and tries to utilize your maximum download bandwidth. By default all the Linux Distribution included aria2, so we can install easily from official repository. some of the GUI download manager using aria2 as a plugin to improve the download speed like [uget][3].
|
||||
[aria2][4] 是一个免费的、开源的、轻量级多协议和多源命令行下载工具。它支持 HTTP/HTTPS、 FTP、 SFTP、 BitTorrent 和 Metalink 协议。aria2 可以通过内建的 JSON-RPC 和 XML-RPC 接口来操纵。aria2 下载文件的时候，自动验证数据块。它可以通过多源或者多协议下载一个文件，并且尝试利用你的最大下载带宽。默认情况下，所有的 Linux 发行版都包括 aria2，所以我们可以从官方库中很容易的安装。一些 GUI 下载管理器例如 [uget][3] 使用 aria2作为一个插件来提高下载速度。
|
||||
|
||||
#### Aria2 Features
|
||||
|
||||
* HTTP/HTTPS GET support
|
||||
* HTTP Proxy support
|
||||
* HTTP BASIC authentication support
|
||||
* HTTP Proxy authentication support
|
||||
* FTP support(active, passive mode)
|
||||
* FTP through HTTP proxy(GET command or tunneling)
|
||||
* Segmented download
|
||||
* Cookie support
|
||||
* It can run as a daemon process.
|
||||
* BitTorrent protocol support with fast extension.
|
||||
* Selective download in multi-file torrent
|
||||
* Metalink version 3.0 support(HTTP/FTP/BitTorrent).
|
||||
* Limiting download/upload speed
|
||||
#### Aria2 特性
|
||||
|
||||
#### 1) Install aria2 on Linux
|
||||
* HTTP/HTTPS GET 支持
|
||||
* HTTP 代理支持
|
||||
* HTTP BASIC 认证支持
|
||||
* HTTP 代理认证支持
|
||||
* FTP 支持（主动、被动模式）
|
||||
* 通过 HTTP 代理的 FTP（GET 命令行或者隧道）
|
||||
* 分段下载
|
||||
* Cookie 支持
|
||||
* 可以作为守护进程运行。
|
||||
* 使用 快速扩展的 BitTorrent 协议支持
|
||||
* 在多 torrent 文件下选择性下载
|
||||
* Metalink 3.0 版本支持（HTTP/FTP/BitTorrent）。
|
||||
* 限制下载、上传速度
|
||||
|
||||
We can easily install aria2 command line downloader to all the Linux Distribution such as Debian, Ubuntu, Mint, RHEL, CentOS, Fedora, suse, openSUSE, Arch Linux, Manjaro, Mageia, etc.. Just fire the below command to install. For CentOS, RHEL systems we need to enable [uget][2] or [RPMForge][1] repository.
|
||||
#### 1) Linux 下安装 aria2
|
||||
|
||||
我们可以很容易的在所有的 Linux 发行版 上安装 aria2 命令行下载器，例如 Debian、 Ubuntu、 Mint、 RHEL、 CentOS、 Fedora、 suse、 openSUSE、 Arch Linux、 Manjaro、 Mageia 等等……只需要输入下面的命令安装即可。对于 CentOS、 RHEL 系统，我们需要开启 [uget][2] 或者 [RPMForge][1] 库的支持。
|
||||
|
||||
```
|
||||
[For Debian, Ubuntu & Mint]
|
||||
[对于 Debian、 Ubuntu 和 Mint]
|
||||
$ sudo apt-get install aria2
|
||||
|
||||
[For CentOS, RHEL, Fedora 21 and older Systems]
|
||||
[对于 CentOS、 RHEL、 Fedora 21 和更早些的操作系统]
|
||||
# yum install aria2
|
||||
|
||||
[Fedora 22 and later systems]
|
||||
[Fedora 22 和 之后的系统]
|
||||
# dnf install aria2
|
||||
|
||||
[For suse & openSUSE]
|
||||
[对于 suse 和 openSUSE]
|
||||
# zypper install wget
|
||||
|
||||
[Mageia]
|
||||
# urpmi aria2
|
||||
|
||||
[For Debian, Ubuntu & Mint]
|
||||
[对于 Debian、 Ubuntu 和 Mint]
|
||||
$ sudo pacman -S aria2
|
||||
|
||||
```
|
||||
|
||||
#### 2) Download Single File
|
||||
#### 2) 下载单个文件
|
||||
|
||||
The below command will download the file from given URL and stores in current directory, while downloading the file we can see the (date, time, download speed & download progress) of file.
|
||||
下面的命令将会从指定的 URL 中下载一个文件，并且保存在当前目录，在下载文件的过程中，我们可以看到文件的（日期、时间、下载速度和下载进度）。
|
||||
|
||||
```
|
||||
# aria2c https://download.owncloud.org/community/owncloud-9.0.0.tar.bz2
|
||||
@ -62,9 +63,9 @@ Status Legend:
|
||||
|
||||
```
|
||||
|
||||
#### 3) Save the file with different name
|
||||
#### 3) 使用不同的名字保存文件
|
||||
|
||||
We can save the file with different name & format while initiate downloading, using -o (lowercase) option. Here we are going to save the filename with owncloud.zip.
|
||||
在初始化下载的时候，我们可以使用 -o（小写）选项在保存文件的时候使用不同的名字。这儿我们将要使用 owncloud.zip 文件名来保存文件。
|
||||
|
||||
```
|
||||
# aria2c -o owncloud.zip https://download.owncloud.org/community/owncloud-9.0.0.tar.bz2
|
||||
@ -81,9 +82,9 @@ Status Legend:
|
||||
|
||||
```
|
||||
|
||||
#### 4) Limit download speed
|
||||
#### 4) 下载速度限制
|
||||
|
||||
By default aria2 utilize full bandwidth for downloading file and we can’t use anything on server before download completion (Which will affect other service accessing bandwidth). So better use –max-download-limit option to avoid further issue while downloading big size file.
|
||||
默认情况下，aria2 利用全带宽限制文件，在文件下载完成之前，我们不可以在服务器上使用任何东西（这将会影响其他服务访问带宽）。所以在下载大文件时最好使用 –max-download-limit 选项来避免进一步的问题。
|
||||
|
||||
```
|
||||
# aria2c --max-download-limit=500k https://download.owncloud.org/community/owncloud-9.0.0.tar.bz2
|
||||
@ -100,9 +101,9 @@ Status Legend:
|
||||
|
||||
```
|
||||
|
||||
#### 5) Download Multiple Files
|
||||
#### 5) 下载多个文件
|
||||
|
||||
The below command will download more then on file from the location and stores in current directory, while downloading the file we can see the (date, time, download speed & download progress) of file.
|
||||
下面的命令将会从指定位置下载不止一个文件并保持到当前目录，在下载文件的过程中，我们可以看到文件的（日期、时间、下载速度和下载进度）。
|
||||
|
||||
```
|
||||
# aria2c -Z https://download.owncloud.org/community/owncloud-9.0.0.tar.bz2 ftp://ftp.gnu.org/gnu/wget/wget-1.17.tar.gz
|
||||
@ -122,11 +123,10 @@ Status Legend:
|
||||
|
||||
```
|
||||
|
||||
#### 6) Resume Incomplete download
|
||||
#### 6) 恢复不完整下载
|
||||
|
||||
Make sure, whenever going to download big size of file (eg: ISO Images), i advise you to use -c option which will help us to resume the existing incomplete download from the state and complete as usual when we are facing any network connectivity issue or system problems. Otherwise when you are download again, it will initiate the fresh download and store to different file name (append .1 to the filename automatically). Note: If any interrupt happen, aria2 save file with .aria2 extension.
|
||||
当你遇到一些网络连接问题或者系统问题的时候，并将要下载一个大文件（例如： ISO 镜像文件），我建议你使用 -c 选项，他可以通过状态帮助我们恢复已经存在的未完成的下载，并且像往常一样完成。不然的话，当你再次下载，它将会初始化新的下载，并保存成一个不同的文件名（自动的在文件名后面添加 .1 ）。注意：如果任意打断发生，aria2 使用 .aria2 后缀保存文件。
|
||||
|
||||
<iframe marginwidth="0" marginheight="0" scrolling="no" frameborder="0" height="90" width="728" id="_mN_gpt_827143833" style="border-width: 0px; border-style: initial; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline;"></iframe>
|
||||
```
|
||||
# aria2c -c https://download.owncloud.org/community/owncloud-9.0.0.tar.bz2
|
||||
[#db0b08 8.2MiB/21MiB(38%) CN:1 DL:3.1MiB ETA:4s]^C
|
||||
@ -142,7 +142,7 @@ db0b08|INPR| 3.3MiB/s|/opt/owncloud-9.0.0.tar.bz2
|
||||
Status Legend:
|
||||
(INPR):download in-progress.
|
||||
|
||||
aria2 will resume download if the transfer is restarted.
|
||||
如果重新启动传输，aria2 将会恢复下载
|
||||
|
||||
# aria2c -c https://download.owncloud.org/community/owncloud-9.0.0.tar.bz2
|
||||
[#873d08 21MiB/21MiB(98%) CN:1 DL:2.7MiB]
|
||||
@ -158,9 +158,9 @@ Status Legend:
|
||||
|
||||
```
|
||||
|
||||
#### 7) Get the input from file
|
||||
#### 7) 从文件获取输入
|
||||
|
||||
Alternatively wget can get the list of input URL’s from file and start downloading. We need to create a file and store each URL in separate line. Add -i option with aria2 command to perform this action.
|
||||
或许 wget 可以从一个文件获取输入的 URL 列表来下载。我们需要创建一个文件，将每一个 URL 存储在单独的行中。ara2 命令行可以添加 -i 选项来执行此操作。
|
||||
|
||||
```
|
||||
# aria2c -i test-aria2.txt
|
||||
@ -180,9 +180,9 @@ Status Legend:
|
||||
|
||||
```
|
||||
|
||||
#### 8) Download using 2 connections per host
|
||||
#### 8) 每个主机使用两个连接来下载
|
||||
|
||||
The maximum number of connections to one server for each download. By default this will establish one connection to each host. We can establish more then one connection to each host to speedup download by adding -x2 (2 means, two connection) option with aria2 command
|
||||
默认情况，每次下载连接到一台服务器的最大数目，对于一条主机只能建立一条。我们可以通过 aria2 命令行添加 -x2（2 表示两个连接）来创建到每台主机多于一个连接，以加快下载速度。
|
||||
|
||||
```
|
||||
# aria2c -x2 https://download.owncloud.org/community/owncloud-9.0.0.tar.bz2
|
||||
@ -199,9 +199,9 @@ Status Legend:
|
||||
|
||||
```
|
||||
|
||||
#### 9) Download Torrent Files
|
||||
#### 9) 下载种子文件
|
||||
|
||||
We can directly download a Torrent files using aria2 command.
|
||||
我们可以使用 aria2 命令行直接下载一个种子文件
|
||||
|
||||
```
|
||||
# aria2c https://torcache.net/torrent/C86F4E743253E0EBF3090CCFFCC9B56FA38451A3.torrent?title=[kat.cr]irudhi.suttru.2015.official.teaser.full.hd.1080p.pathi.team.sr
|
||||
@ -221,27 +221,27 @@ Status Legend:
|
||||
|
||||
```
|
||||
|
||||
#### 10) Download BitTorrent Magnet URI
|
||||
#### 10) 下载 Bit 种子磁力链接
|
||||
|
||||
Also we can directly download a Torrent files through BitTorrent Magnet URI using aria2 command.
|
||||
使用 aria2 我们也可以通过 bit 磁力链接直接下载一个种子文件
|
||||
|
||||
```
|
||||
# aria2c 'magnet:?xt=urn:btih:248D0A1CD08284299DE78D5C1ED359BB46717D8C'
|
||||
|
||||
```
|
||||
|
||||
#### 11) Download BitTorrent Metalink
|
||||
#### 11) 下载 Metalink Bit 种子
|
||||
|
||||
Also we can directly download a Metalink file using aria2 command.
|
||||
我们也可以通过 aria2 命令行直接下载一个 Metalink 文件。
|
||||
|
||||
```
|
||||
# aria2c https://curl.haxx.se/metalink.cgi?curl=tar.bz2
|
||||
|
||||
```
|
||||
|
||||
#### 12) Download a file from password protected site
|
||||
#### 12) 从密码保护的网站下载一个文件
|
||||
|
||||
Alternatively we can download a file from password protected site. The below command will download the file from password protected site.
|
||||
或者，我们也可以从一个密码保护网站下载一个文件。下面的命令行将会从一个密码保护网站中下载文件。
|
||||
|
||||
```
|
||||
# aria2c --http-user=xxx --http-password=xxx https://download.owncloud.org/community/owncloud-9.0.0.tar.bz2
|
||||
@ -250,9 +250,9 @@ Alternatively we can download a file from password protected site. The below com
|
||||
|
||||
```
|
||||
|
||||
#### 13) Read more about aria2
|
||||
#### 13) 阅读更多关于 aria2
|
||||
|
||||
If you want to know more option which is available for wget, you can grep the details on your terminal itself by firing below commands..
|
||||
如果你希望了解了解更多选项 —— 它们同时适用于 wget，可以输入下面的命令行在你自己的终端获取详细信息：
|
||||
|
||||
```
|
||||
# man aria2c
|
||||
@ -261,7 +261,7 @@ or
|
||||
|
||||
```
|
||||
|
||||
Enjoy…)
|
||||
谢谢欣赏 …）
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
@ -269,7 +269,7 @@ via: http://www.2daygeek.com/aria2-command-line-download-utility-tool/
|
||||
|
||||
作者：[MAGESH MARUTHAMUTHU][a]
|
||||
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
译者：[yangmingming](https://github.com/yangmingming)
|
||||
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
455
translated/tech/20161027 DTrace for Linux 2016.md
Normal file
455
translated/tech/20161027 DTrace for Linux 2016.md
Normal file
@ -0,0 +1,455 @@
|
||||
Linux 中的 DTrace
|
||||
===========
|
||||
|
||||
|
||||
|
||||
随着 BPF 追踪系统（基于时间采样）最后一个主要功能被合并至 Linux 4.9-rc1 版本的内核中，现在 Linux 内核拥有类似 DTrace 的原生追踪功能。DTrace 是 Solaris 系统中的高级追踪器。对于长期使用 DTrace 的用户和专家，这将是一个振奋人心的里程碑！在 Linux 系统上，现在你可以使用用安全的、低负载的定制追踪系统，通过执行时间的柱状图和频率统计等信息，分析应用的性能以及内核。
|
||||
|
||||
用于 Linux 的追踪工程有很多，但是最终被合并进 Linux 内核的技术从一开始就根本不是一个追踪项目：它是最开始是用于 Berkeley Packet Filter（BPF）的补丁。这些补丁允许 BPF 将软件包重定向，创建软件定义的网络。久而久之，支持追踪事件就被添加进来了，使得程序追踪可用于 Linux 系统。
|
||||
|
||||
尽管目前 BPF 没有像 DTrace 一样的高级语言，它所提供的前端已经足够让我创建很多 BPF 工具了，其中有些是基于我以前的 [DTraceToolkit][37]。这个帖子将告诉你怎么去用这些工具，BPF 提供的前端，以及畅谈这项技术将会何去何从。
|
||||
|
||||
### 截图
|
||||
|
||||
我已经将基于 BPF 的追踪工具添加到了开源的 [bcc][36] 项目里（感谢 PLUMgrid 公司的 Brenden Blanco 带领 bcc 项目的发展）。详见 [bcc 安装][35] 手册。它会在 /usr/share/bcc/tools 目录下添加一系列工具，包括接下来的那些工具。
|
||||
|
||||
捕获新进程：
|
||||
|
||||
```
|
||||
# **execsnoop**
|
||||
PCOMM PID RET ARGS
|
||||
bash 15887 0 /usr/bin/man ls
|
||||
preconv 15894 0 /usr/bin/preconv -e UTF-8
|
||||
man 15896 0 /usr/bin/tbl
|
||||
man 15897 0 /usr/bin/nroff -mandoc -rLL=169n -rLT=169n -Tutf8
|
||||
man 15898 0 /usr/bin/pager -s
|
||||
nroff 15900 0 /usr/bin/locale charmap
|
||||
nroff 15901 0 /usr/bin/groff -mtty-char -Tutf8 -mandoc -rLL=169n -rLT=169n
|
||||
groff 15902 0 /usr/bin/troff -mtty-char -mandoc -rLL=169n -rLT=169n -Tutf8
|
||||
groff 15903 0 /usr/bin/grotty
|
||||
|
||||
```
|
||||
|
||||
硬盘 I/O 延迟的柱状图：
|
||||
|
||||
```
|
||||
# **biolatency -m**
|
||||
Tracing block device I/O... Hit Ctrl-C to end.
|
||||
^C
|
||||
msecs : count distribution
|
||||
0 -> 1 : 96 |************************************ |
|
||||
2 -> 3 : 25 |********* |
|
||||
4 -> 7 : 29 |*********** |
|
||||
8 -> 15 : 62 |*********************** |
|
||||
16 -> 31 : 100 |**************************************|
|
||||
32 -> 63 : 62 |*********************** |
|
||||
64 -> 127 : 18 |****** |
|
||||
|
||||
```
|
||||
|
||||
追踪常见的 ext4 操作，稍慢于 5ms：
|
||||
|
||||
```
|
||||
# **ext4slower 5**
|
||||
Tracing ext4 operations slower than 5 ms
|
||||
TIME COMM PID T BYTES OFF_KB LAT(ms) FILENAME
|
||||
21:49:45 supervise 3570 W 18 0 5.48 status.new
|
||||
21:49:48 supervise 12770 R 128 0 7.55 run
|
||||
21:49:48 run 12770 R 497 0 16.46 nsswitch.conf
|
||||
21:49:48 run 12770 R 1680 0 17.42 netflix_environment.sh
|
||||
21:49:48 run 12770 R 1079 0 9.53 service_functions.sh
|
||||
21:49:48 run 12772 R 128 0 17.74 svstat
|
||||
21:49:48 svstat 12772 R 18 0 8.67 status
|
||||
21:49:48 run 12774 R 128 0 15.76 stat
|
||||
21:49:48 run 12777 R 128 0 7.89 grep
|
||||
21:49:48 run 12776 R 128 0 8.25 ps
|
||||
21:49:48 run 12780 R 128 0 11.07 xargs
|
||||
21:49:48 ps 12776 R 832 0 12.02 libprocps.so.4.0.0
|
||||
21:49:48 run 12779 R 128 0 13.21 cut
|
||||
[...]
|
||||
|
||||
```
|
||||
|
||||
追踪新建的 TCP 活跃连接（connect()）:
|
||||
|
||||
```
|
||||
# **tcpconnect**
|
||||
PID COMM IP SADDR DADDR DPORT
|
||||
1479 telnet 4 127.0.0.1 127.0.0.1 23
|
||||
1469 curl 4 10.201.219.236 54.245.105.25 80
|
||||
1469 curl 4 10.201.219.236 54.67.101.145 80
|
||||
1991 telnet 6 ::1 ::1 23
|
||||
2015 ssh 6 fe80::2000:bff:fe82:3ac fe80::2000:bff:fe82:3ac 22
|
||||
|
||||
```
|
||||
|
||||
通过捕获 getaddrinfo()/gethostbyname() 库的调用来追踪 DNS 延迟：
|
||||
|
||||
```
|
||||
# **gethostlatency**
|
||||
TIME PID COMM LATms HOST
|
||||
06:10:24 28011 wget 90.00 www.iovisor.org
|
||||
06:10:28 28127 wget 0.00 www.iovisor.org
|
||||
06:10:41 28404 wget 9.00 www.netflix.com
|
||||
06:10:48 28544 curl 35.00 www.netflix.com.au
|
||||
06:11:10 29054 curl 31.00 www.plumgrid.com
|
||||
06:11:16 29195 curl 3.00 www.facebook.com
|
||||
06:11:25 29404 curl 72.00 foo
|
||||
06:11:28 29475 curl 1.00 foo
|
||||
|
||||
```
|
||||
|
||||
按类别划分 VFS 操作的时间间隔统计：
|
||||
|
||||
```
|
||||
# **vfsstat**
|
||||
TIME READ/s WRITE/s CREATE/s OPEN/s FSYNC/s
|
||||
18:35:32: 231 12 4 98 0
|
||||
18:35:33: 274 13 4 106 0
|
||||
18:35:34: 586 86 4 251 0
|
||||
18:35:35: 241 15 4 99 0
|
||||
|
||||
```
|
||||
|
||||
对一个给定的 PID，通过内核和用户堆栈轨迹来追踪 CPU 外的时间（由内核进行统计）：
|
||||
|
||||
```
|
||||
# **offcputime -d -p 24347**
|
||||
Tracing off-CPU time (us) of PID 24347 by user + kernel stack... Hit Ctrl-C to end.
|
||||
^C
|
||||
[...]
|
||||
ffffffff810a9581 finish_task_switch
|
||||
ffffffff8185d385 schedule
|
||||
ffffffff81085672 do_wait
|
||||
ffffffff8108687b sys_wait4
|
||||
ffffffff81861bf6 entry_SYSCALL_64_fastpath
|
||||
--
|
||||
00007f6733a6b64a waitpid
|
||||
- bash (24347)
|
||||
4952
|
||||
|
||||
ffffffff810a9581 finish_task_switch
|
||||
ffffffff8185d385 schedule
|
||||
ffffffff81860c48 schedule_timeout
|
||||
ffffffff810c5672 wait_woken
|
||||
ffffffff8150715a n_tty_read
|
||||
ffffffff815010f2 tty_read
|
||||
ffffffff8122cd67 __vfs_read
|
||||
ffffffff8122df65 vfs_read
|
||||
ffffffff8122f465 sys_read
|
||||
ffffffff81861bf6 entry_SYSCALL_64_fastpath
|
||||
--
|
||||
00007f6733a969b0 read
|
||||
- bash (24347)
|
||||
1450908
|
||||
|
||||
```
|
||||
|
||||
追踪 MySQL 查询延迟（通过 USDT 探针）：
|
||||
|
||||
```
|
||||
# **mysqld_qslower `pgrep -n mysqld`**
|
||||
Tracing MySQL server queries for PID 14371 slower than 1 ms...
|
||||
TIME(s) PID MS QUERY
|
||||
0.000000 18608 130.751 SELECT * FROM words WHERE word REGEXP '^bre.*n$'
|
||||
2.921535 18608 130.590 SELECT * FROM words WHERE word REGEXP '^alex.*$'
|
||||
4.603549 18608 24.164 SELECT COUNT(*) FROM words
|
||||
9.733847 18608 130.936 SELECT count(*) AS count FROM words WHERE word REGEXP '^bre.*n$'
|
||||
17.864776 18608 130.298 SELECT * FROM words WHERE word REGEXP '^bre.*n$' ORDER BY word
|
||||
|
||||
```
|
||||
|
||||
<!--Using the trace multi-tool to watch login requests, by instrumenting the pam library: -->
|
||||
检测 pam 库并使用多种追踪工具观察登陆请求：
|
||||
|
||||
```
|
||||
# **trace 'pam:pam_start "%s: %s", arg1, arg2'**
|
||||
TIME PID COMM FUNC -
|
||||
17:49:45 5558 sshd pam_start sshd: root
|
||||
17:49:47 5662 sudo pam_start sudo: root
|
||||
17:49:49 5727 login pam_start login: bgregg
|
||||
|
||||
```
|
||||
|
||||
bcc 项目里的很多工具都有帮助信息（-h 选项），并且都应该包含有示例的 man 页面和文本文件。
|
||||
|
||||
### 必要的
|
||||
|
||||
2014 年，Linux 追踪程序就有一些内核相关的特性（自 ftrace 和 pref_events），但是我们仍然要转储并报告进程数据，因为数十年的老技术会有很大规模的开销。你不能频繁地访问进程名，函数名，堆栈轨迹或内核中的其它任何数据。你不能在将变量保存到一个监测事件里，又在另一个事件里访问它们，这意味着你不能在自定义的地方计算延迟（或者说时间参数）。你也不能创建一个内核之内的延迟柱状图，也不能追踪 USDT 探针，甚至不能写自定义的程序。DTrace 可以做到这些，但仅限于 Solaris 或 BSD 系统。在 Linux 系统中，有些基于树的追踪器，像 SystemTap 就可以满足你的这些需求，但它也有自身的不足。（你可以写一个基于探针的内核模块来满足需求-但实际上没人这么做。）
|
||||
|
||||
2014 年我加入了 Netflix cloud performance 团队。做了这么久的 DTrace 方面的专家，转到 Linux 对我来说简直不可思议。但我确实这么做了，尤其是发现了严重的问题：Netflix cloud 会随着应用，微服务架构和分布式系统的快速变化，性能受到影响。有时要用到系统追踪，而我之前是用的 DTrace。在 Linux 系统上可没有 DTrace，我就开始用 Linux 内核内建的 ftrace 和 perf_events 工具，构建了一个追踪工具（[perf-tools][34]）。这些工具很有用，但有些工作还是没法完成，尤其是延迟柱状图图以及计算堆栈踪迹。我们需要的是内核追踪程序化。
|
||||
|
||||
### 发生了什么？
|
||||
|
||||
BPF 将程序化的功能添加到现有的内核追踪工具中（tracepoints, kprobes, uprobes）。在 Linux 4.x 系列的内核里，这些功能大大加强了。
|
||||
|
||||
时间采样是最主要的部分，它被 Linux 4.9-rc1 所采用（[patchset][33]）。十分感谢 Alexei Starovoitov（致力于 Facebook 中的 BPF 开发），改进 BPF 的主要开发者。
|
||||
|
||||
Linux 内核现在内建有以下这些特性（添加自 2.6 版本到 4.9 版本）：
|
||||
|
||||
* 内核级的动态追踪（BPF 对 kprobes 的支持）
|
||||
* 用户级的动态追踪（BPF 对 uprobes 的支持）
|
||||
* 内核级的静态追踪（BPF 对 tracepoints 的支持）
|
||||
* 时间采样事件（BPF 的 pref_event_open）
|
||||
* PMC 事件（BPF 的 pref_event_open）
|
||||
* 过滤器（通过 BPF 程序）
|
||||
* 调试输出（bpf_trace_printk()）
|
||||
* 事件输出（bpf_perf_event_output()）
|
||||
* 基础变量（全局的和每个线程的变量，基于 BPF 映射）
|
||||
* 关联数组（通过 BPF 映射）
|
||||
* 频率计数（基于 BPF 映射）
|
||||
* 柱状图（power-of-2, 线性及自定义，基于 BPF 映射）
|
||||
* Timestamps and time deltas (bpf_ktime_get_ns(), and BPF programs)
|
||||
* 时间戳和时间参数（bpf_ktime_get_ns()，和 BPF 程序）
|
||||
* 内核态的堆栈轨迹（BPF stackmap 栈映射）
|
||||
* 用户态的堆栈轨迹 (BPF stackmap 栈映射)
|
||||
* 重写 ring 缓存（pref_event_attr.write_backward）
|
||||
|
||||
我们采用的前端是 bcc，它同时提供 Python 和 lua 接口。bcc 添加了：
|
||||
|
||||
* 用户级静态追踪（基于 uprobes 的 USDT 探针）
|
||||
* 调试输出（调用 BPF.trace_pipe() 和 BPF.trace_fields() 函数的 Python）
|
||||
* 所有事件输出（BPF_PERF_OUTPUT 宏和 BPF.open_perf_buffer()）
|
||||
* 间隔输出（BPF.get_table() 和 table.clear()）
|
||||
* 打印柱状图（table.print_log2_hist()）
|
||||
* 内核级的 C 结构体导航（bcc 重写 bpf_probe_read() 函数的映射）
|
||||
* 内核级的符号解析（ksym(), ksymaddr()）
|
||||
* 用户级的符号解析（usymaddr()）
|
||||
* BPF tracepoint 支持（通过 TRACEPOINT_PROBE）
|
||||
* BPF 堆栈轨迹支持（包括针对堆栈框架的 walk 方法）
|
||||
* 其它各种助手宏和方法
|
||||
* 例子（位于 /examples 目录）
|
||||
* 工具（位于 /tools 目录）
|
||||
* 教程（/docs/tutorial*.md）
|
||||
* 参考手册（/docs/reference_guide.md）
|
||||
|
||||
直到最新也是最主要的特性被整合进来，我才开始写这篇文章，现在它在 4.9-rc1 内核中。我们还需要去完成一些次要的东西，还有另外一些事情要做，但是现在我们所拥有的已经值得欢呼了。现在 Linux 拥有内建的高级追踪能力。
|
||||
|
||||
### 安全性
|
||||
|
||||
设计 BPF 以及改进版时就考虑到产品安全，它被用在大范围的生产环境里。确信的话，你应该能找到一个挂起内核的方法。这个例子是偶然而不是必然，类似的漏洞会被快速修复，尤其是当 BPF 合并入了 Linux。因为 Linux 可是公众的焦点。
|
||||
|
||||
在开发过程中我们碰到了一些非 BPF 的漏洞，它们需要被修复：rcu 不可重入，这可能导致内核由于 funccount 挂起，在 4.6 内核版本中这个漏洞被 “bpf: map pre-alloc” 所修复，旧版本内核的漏洞暂时由 bcc 处理。还有一个是 uprobe 的内存计算问题，这导致 uprobe 分配内存失败，在 4.8 内核版本这个漏洞由 “uprobes: Fix the memcg accounting” 补丁所修复，并且该补丁还将被移植到之前版本的内核中（例如，它现在被移植到了 4.4.27 和 4.4.0-45.66 版本中）。
|
||||
|
||||
### 为什么 Linux 追踪很耗时？
|
||||
|
||||
首要任务被分到了若干追踪器中间：只有联合使用这些追踪器才能有作用。想要了解更多关于这个或其它方面的问题，可以看一看我在 2014 年写的 [tracing summit talk][32]。我忽视了计数器在部分方案中的效率：有些公司发现其它追踪器（SystemTap 和 LTTng）能满足他们的需求，尽管他们乐于听到 BPF 的开发进程，考虑到他们现有的解决方案，帮助 BPF 的开发就不那么重要了。
|
||||
|
||||
近两年里 BPF 仅在追踪领域得到加强。这一过程原本可以更快的，但早期缺少全职工作于 BPF 追踪的工程师。Alexei Starovoitov (BPF 领导者)，Brenden Blanco (bcc 领导者)，我还有其它一些开发者，都有其它的事情要做。我在 Netflix 公司花了大量时间（自由工作地），大概有 7% 的时间是花在 BPF 和 bcc 上。某种程度上这不是我的首要任务，因为我还有自己的工作（包括我的 perf-tools，一个工作在旧版本内核上的程序）。
|
||||
|
||||
BPF 追踪已经推出了，已经有科技公司开始关注 BPF 的特点了。但我还是推荐 [Netflix 公司][31]。（如果你为了 BPF 而要聘请我，那我还是十分乐于待在 Netflix 公司的！）
|
||||
|
||||
### 使用简单
|
||||
|
||||
DTrace 和 bcc/BPF 现在的最大区别就是哪个更好使用。这取决于你要用 BPF 追踪做什么了。如果你要
|
||||
|
||||
* **使用 BPF tools/metrics**：应该是没什么区别的。工具的表现都差不多，图形用户界面的访问也类似。大部分用户通过这种方式使用 BPF。
|
||||
* **开发 tools/metrics**：bcc 的开发可难多了。DTrace 有一套自己的简单语言，D 语音，和 awk 语言相似，而 bcc 使用已有的带有库的语言（C 语言，Python 和 lua）。一个用 C 和 Python 写的 bcc 工具与仅仅用 D 语言写出来的工具相比，可能要多十多倍行数的代码，或者更多。但是很多 DTrace 工具用 shell 包装来提供参数和差错，会让代码变得十分臃肿。编程的难处是不同的：重写 bcc 更需要巧妙性，这导致某些脚本更加难开发。（尤其是 bpf_probe_read() 这类的函数，需要了解更多 BPF 的内涵知识）。当计划改进 bcc 时，这一情形将得到改善。
|
||||
* **运行常见的命令**：十分相近。用 “dtrace” 命令，DTrace 能做很多事，但 bcc 有各种工具，trace，argdist，funccount，funclatency 等等。
|
||||
* **编写自定义的特殊命令**：使用 DTrace 的话，这就没有必要了。允许定制消息快速传递和系统快速响应，DTrace 的高级分析很快。而 bcc 现在受限于它的多种工具以及它们的适用范围。
|
||||
|
||||
简单来说，如果你只使用 BPF 工具的话，就不必关注这些差异了。如果你经验丰富，是个开发者（像我一样），目前 bcc 的使用是比较困难的。
|
||||
|
||||
举一个 bcc 的 Python 前端的例子，下面是追踪硬盘 I/O 和 打印 I/O 容量柱状图的代码：
|
||||
|
||||
```
|
||||
from bcc import BPF
|
||||
from time import sleep
|
||||
|
||||
# load BPF program
|
||||
b = BPF(text="""
|
||||
#include <uapi/linux/ptrace.h>
|
||||
#include <linux/blkdev.h>
|
||||
|
||||
BPF_HISTOGRAM(dist);
|
||||
|
||||
int kprobe__blk_account_io_completion(struct pt_regs *ctx, struct request *req)
|
||||
{
|
||||
dist.increment(bpf_log2l(req->__data_len / 1024));
|
||||
return 0;
|
||||
}
|
||||
""")
|
||||
|
||||
# header
|
||||
print("Tracing... Hit Ctrl-C to end.")
|
||||
|
||||
# trace until Ctrl-C
|
||||
try:
|
||||
sleep(99999999)
|
||||
except KeyboardInterrupt:
|
||||
print
|
||||
|
||||
# output
|
||||
b["dist"].print_log2_hist("kbytes")
|
||||
|
||||
```
|
||||
|
||||
注意 Python 代码中嵌入的 C 语句（text=）。
|
||||
|
||||
这就完成了任务，但仍有改进的空间。好在我们有时间去做：人们使用 Linux 4.9 并能用上 BPF 还得好几个月呢，所以我们有时间来制造工具和前端。
|
||||
|
||||
### 高级语言
|
||||
|
||||
前端越简单，比如高级语言，所改进的可能就越不如你所期望的。绝大多数人使用封装好的工具（和 GUI），仅有少部分人能写出这些工具。但我不反对使用高级语言，比如 SystemTap，毕竟已经开发出来了。
|
||||
|
||||
```
|
||||
#!/usr/bin/stap
|
||||
/*
|
||||
* opensnoop.stp Trace file open()s. Basic version of opensnoop.
|
||||
*/
|
||||
|
||||
probe begin
|
||||
{
|
||||
printf("\n%6s %6s %16s %s\n", "UID", "PID", "COMM", "PATH");
|
||||
}
|
||||
|
||||
probe syscall.open
|
||||
{
|
||||
printf("%6d %6d %16s %s\n", uid(), pid(), execname(), filename);
|
||||
}
|
||||
|
||||
```
|
||||
|
||||
如果拥有整合了语言和脚本的 SystemTap 前端与高性能内核内建的 BPF 后端，会不会令人满意呢？RedHat 公司的 Richard Henderson 已经在进行相关工作了，并且发布了 [初代版本][30]！
|
||||
|
||||
这是 [ply][29],一个完全新颖的 BPF 高级语言：
|
||||
|
||||
```
|
||||
#!/usr/bin/env ply
|
||||
|
||||
kprobe:SyS_*
|
||||
{
|
||||
$syscalls[func].count()
|
||||
}
|
||||
|
||||
```
|
||||
|
||||
这也是一份承诺。
|
||||
|
||||
尽管如此，我认为工具开发者的实际难题不是使用什么语言：而是要了解要用这些强大的工具做什么？
|
||||
|
||||
### 如何帮助我们
|
||||
|
||||
* **推广**：BPF 追踪目前还没有什么市场方面的进展。尽管有公司了解并在使用它（Facebook，Netflix，Github 和其它公司），但要广为人知尚需时日。分享关于 BPF 产业的文章和资源来帮助我们。
|
||||
* **教育**：你可以撰写文章，发表演讲，甚至参与 bcc 文档的编写。分享 BPF 如何解决实际问题以及为公司带来收益的实例。
|
||||
* **解决 bcc 的问题**：参考 [bcc issue list][19]，这包含了错误和需要的特性。
|
||||
* **提交错误**：使用 bcc/BPF，提交你发现的错误。
|
||||
* **创造工具**：有很多可视化的工具需要开发，请不要太草率，因为大家会先花几个小时学习使用你做的工具，所以请尽量把工具做的直观好用（参考我的 [文档][18]）。就像 Mike Muuss 提及到他自己的 [ping][17] 程序：“要是我早知道这是我一生中最出名的成就，我就多开发一两天，添加更多选项。”
|
||||
* **高级语言**：如果现有的 bcc 前端语言让你很困扰，或者你能弄门更好的语言。要是你想将这门语言内建到 bcc 里面，你需要使用 libbcc。或者你可以帮助进行 SystemTap BPF 或 ply 的工作。
|
||||
* **整合图形界面**：除了 bcc 可以使用的 CLI 命令行工具，怎么让这些信息可视呢？延迟关系，火焰图等等。
|
||||
|
||||
### 其它追踪器
|
||||
|
||||
那么 SystemTap，ktap，sysdig，LTTng 等追踪器怎么样呢？它们有个共同点，要么使用了 BPF，要么在自己的领域做得更好。会有单独的文章介绍它们自己。
|
||||
|
||||
至于 DTrace ？我们公司目前还在基于 FreeBSD 系统的 CDN 中使用它。
|
||||
|
||||
### 更多 bcc/BPF 的信息
|
||||
|
||||
我已经写了一篇 [bcc/BPF Tool End-User Tutorial][28]，一篇 [bcc Python Developer's Tutorial][27]，一篇 [bcc/BPF Reference Guide][26]，和已经写好的有用的 [/tools][25]，每一个工具都有一个 [example.txt][24] 文件和 [man page][23]。我之前写过的关于 bcc 和 BPF 的文章有：
|
||||
|
||||
* [eBPF: One Small Step][16] （以后就叫做 BPF）
|
||||
* [bcc: Taming Linux 4.3+ Tracing Superpowers][15]
|
||||
* [Linux eBPF Stack Trace Hack][14] （现在官方支持追踪堆栈了）
|
||||
* [Linux eBPF Off-CPU Flame Graph][13] (" " ")
|
||||
* [Linux Wakeup and Off-Wake Profiling][12] (" " ")
|
||||
* [Linux Chain Graph Prototype][11] (" " ")
|
||||
* [Linux eBPF/bcc uprobes][10]
|
||||
* [Linux BPF Superpowers][9]
|
||||
* [Ubuntu Xenial bcc/BPF][8]
|
||||
* [Linux bcc Tracing Security Capabilities][7]
|
||||
* [Linux MySQL Slow Query Tracing with bcc/BPF][6]
|
||||
* [Linux bcc ext4 Latency Tracing][5]
|
||||
* [Linux bcc/BPF Run Queue (Scheduler) Latency][4]
|
||||
* [Linux bcc/BPF Node.js USDT Tracing][3]
|
||||
* [Linux bcc tcptop][2]
|
||||
* [Linux 4.9's Efficient BPF-based Profiler][1]
|
||||
|
||||
我在 Facebook 的 Performance@Scale [Linux BPF Superpowers][22] 大会上发表过一次演讲。十二月份，我将在 Boston 发表关于 BPF/bcc 在 [USENIX LISA][21] 方面的演讲和教程。
|
||||
|
||||
### 致谢
|
||||
|
||||
* Van Jacobson and Steve McCanne，他是最早将 BPF 应用到包过滤的。
|
||||
* Barton P. Miller，Jeffrey K. Hollingsworth，and Jon Cargille，发明了动态追踪，并发表文章《Dynamic Program Instrumentation for Scalable Performance Tools》，可扩展高性能计算协议 （SHPCC），于田纳西州诺克斯维尔市，1994 年 5 月发表。
|
||||
* kerninst (ParaDyn, UW-Madison), an early dynamic tracing tool that showed the value of dynamic tracing (late 1990's).（早期的能够显示动态追踪数值的动态追踪工具，稍晚于 1990 年）
|
||||
* Mathieu Desnoyers (of LTTng)，内核的主要开发者，主导 tracepoints 项目。
|
||||
* IBM 开发的作为 DProbes 一部分的 kprobes，DProbes 在 2000 年时曾与 LTT 一起提供 Linux 动态追踪，但没有整合到一起。
|
||||
* Bryan Cantrill, Mike Shapiro, and Adam Leventhal (Sun Microsystems)，DTrace 的核心成员，DTrace 是一款很棒的动态追踪工具，安全而且简单（2004 年）。考虑到动态追踪的技术，DTrace 是科技的重要转折点：它很安全，默认安装在 Solaris 以及其它以可靠性著称的系统里。
|
||||
* 来自 Sun Microsystems 的各部门的许多员工，促进了 DTrace，为我们带来了高级系统追踪的意识。
|
||||
* Roland McGrath (at Red Hat)，utrace 项目的主要开发者，utrace 变成了后来的 uprobes。
|
||||
* Alexei Starovoitov (PLUMgrid, then Facebook), 加强版 BPF（可编程内核容器）的主要开发者。
|
||||
* 那些帮助反馈，提交代码、测试以及针对增强版 BPF 补丁（搜索 BPF 的 lkml）的 Linux 内核工程师： Wang Nan, Daniel Borkmann, David S. Miller, Peter Zijlstra, 以及其它很多人。
|
||||
* Brenden Blanco (PLUMgrid)，bcc 的主要开发者。
|
||||
* Sasha Goldshtein (Sela) 开发了 bcc 中可用的 tracepoint，和功能最强大的 bcc 工具 trace 及 argdist，帮助 USDT 项目的开发。
|
||||
* Vicent Martí 和其它 Github 上的工程师，为 bcc 编写了基于 lua 的前端，帮助 USDT 部分项目的开发。
|
||||
* Allan McAleavy, Mark Drayton，和其他的改进 bcc 的贡献者。
|
||||
|
||||
感觉 Netflix 提供环的境和支持，让我能够编写 BPF 和 bcc tracing 并完成它们。开发追踪工具（使用 TNF/prex, DTrace, SystemTap, ktap, ftrace, perf, and now bcc/BPF）和写书、博客以及评论，我已经编写了多年的追踪工具。
|
||||
|
||||
最后，感谢 [Deirdré][20] 编辑了另外一篇文章。
|
||||
|
||||
### 总结
|
||||
|
||||
Linux 没有 DTrace（语言），但它现在有了，或者说拥有了 DTraceTookit（工具）。
|
||||
|
||||
通过内核构建的 BPF 引擎补丁，Linux 4.9 内核有用来支持现代化追踪的最后一项功能。内核支持这一最难的部分已经做完了。今后的任务包括更多的命令行执行工具，可选的高级语言和图形用户界面。
|
||||
|
||||
对于性能分析产品的客户，这也是一件好事：你能查看延迟柱状图和热点图，CPU 运行和休眠的火焰图，拥有更好的时延断点和更低耗的工具。我们现在用的追踪和处理程序是没有效率的方式。
|
||||
|
||||
那么你什么时候会升级到 Linux 4.9 呢？一旦官方发布，新的性能测试工具就来了：`apt-get install bcc-tools` 。
|
||||
|
||||
开始享受它吧!
|
||||
|
||||
Brendan
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: http://www.brendangregg.com/blog/2016-10-27/dtrace-for-linux-2016.html
|
||||
|
||||
作者：[Brendan Gregg][a]
|
||||
|
||||
译者：[GitFuture](https://github.com/GitFuture)
|
||||
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:http://www.brendangregg.com/
|
||||
[1]:http://www.brendangregg.com/blog/2016-10-21/linux-efficient-profiler.html
|
||||
[2]:http://www.brendangregg.com/blog/2016-10-15/linux-bcc-tcptop.html
|
||||
[3]:http://www.brendangregg.com/blog/2016-10-12/linux-bcc-nodejs-usdt.html
|
||||
[4]:http://www.brendangregg.com/blog/2016-10-08/linux-bcc-runqlat.html
|
||||
[5]:http://www.brendangregg.com/blog/2016-10-06/linux-bcc-ext4dist-ext4slower.html
|
||||
[6]:http://www.brendangregg.com/blog/2016-10-04/linux-bcc-mysqld-qslower.html
|
||||
[7]:http://www.brendangregg.com/blog/2016-10-01/linux-bcc-security-capabilities.html
|
||||
[8]:http://www.brendangregg.com/blog/2016-06-14/ubuntu-xenial-bcc-bpf.html
|
||||
[9]:http://www.brendangregg.com/blog/2016-03-05/linux-bpf-superpowers.html
|
||||
[10]:http://www.brendangregg.com/blog/2016-02-08/linux-ebpf-bcc-uprobes.html
|
||||
[11]:http://www.brendangregg.com/blog/2016-02-05/ebpf-chaingraph-prototype.html
|
||||
[12]:http://www.brendangregg.com/blog/2016-02-01/linux-wakeup-offwake-profiling.html
|
||||
[13]:http://www.brendangregg.com/blog/2016-01-20/ebpf-offcpu-flame-graph.html
|
||||
[14]:http://www.brendangregg.com/blog/2016-01-18/ebpf-stack-trace-hack.html
|
||||
[15]:http://www.brendangregg.com/blog/2015-09-22/bcc-linux-4.3-tracing.html
|
||||
[16]:http://www.brendangregg.com/blog/2015-05-15/ebpf-one-small-step.html
|
||||
[17]:http://ftp.arl.army.mil/~mike/ping.html
|
||||
[18]:https://github.com/iovisor/bcc/blob/master/CONTRIBUTING-SCRIPTS.md
|
||||
[19]:https://github.com/iovisor/bcc/issues
|
||||
[20]:http://www.brendangregg.com/blog/2016-07-23/deirdre.html
|
||||
[21]:https://www.usenix.org/conference/lisa16
|
||||
[22]:http://www.brendangregg.com/blog/2016-03-05/linux-bpf-superpowers.html
|
||||
[23]:https://github.com/iovisor/bcc/tree/master/man/man8
|
||||
[24]:https://github.com/iovisor/bcc/tree/master/tools
|
||||
[25]:https://github.com/iovisor/bcc/tree/master/tools
|
||||
[26]:https://github.com/iovisor/bcc/blob/master/docs/reference_guide.md
|
||||
[27]:https://github.com/iovisor/bcc/blob/master/docs/tutorial_bcc_python_developer.md
|
||||
[28]:https://github.com/iovisor/bcc/blob/master/docs/tutorial.md
|
||||
[29]:https://wkz.github.io/ply/
|
||||
[30]:https://lkml.org/lkml/2016/6/14/749
|
||||
[31]:http://www.brendangregg.com/blog/2016-03-30/working-at-netflix-2016.html
|
||||
[32]:http://www.slideshare.net/brendangregg/from-dtrace-to-linux
|
||||
[33]:https://lkml.org/lkml/2016/9/1/831
|
||||
[34]:https://github.com/brendangregg/perf-tools
|
||||
[35]:https://github.com/iovisor/bcc/blob/master/INSTALL.md
|
||||
[36]:https://github.com/iovisor/bcc
|
||||
[37]:https://github.com/opendtrace/toolkit
|
||||
[38]:https://raw.githubusercontent.com/brendangregg/bcc/master/images/bcc_tracing_tools_2016.png
|
||||
@ -0,0 +1,212 @@
|
||||
翻译完成 by zky001
|
||||
|
||||
如何通过最后修改的日期和时间对ls命令的输出进行排序
|
||||
|
||||
============================================================
|
||||
|
||||
Linux用户常常做的一个事情是，是在命令行[列出目录内容][1]。
|
||||
|
||||
我们已经知道，[ls][2]和[dir][3]是两个可用在列出目录内容的Linux命令，前者是更受欢迎的，在大多数情况下，是用户的首选。
|
||||
|
||||
我们列出目录内容，可以按照不同的标准进行排序，例如文件名，修改时间，添加时间，版本或者文件大小。
|
||||
|
||||
可以通过指定一个特别的参数来使用这些文件的属性进行排序。
|
||||
|
||||
在这个简洁的[ls命令指导][4]中，我们将看看如何通过上次修改时间 (日期和时分秒)[排序ls命令的输出结果][5] 。
|
||||
|
||||
让我们由执行一些基本的[ls命令][6]开始
|
||||
|
||||
### Linux基本ls命令
|
||||
|
||||
|
||||
|
||||
1. 不带任何参数运行ls命令将列出当前工作目录的内容。
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
```
|
||||
|
||||
$ ls
|
||||
|
||||
```
|
||||
|
||||
[][7]
|
||||
|
||||
|
||||
|
||||
列出工作目录的内容
|
||||
|
||||
|
||||
|
||||
2.要列出任何目录的内容，例如 /etc 目录使用：
|
||||
|
||||
|
||||
|
||||
```
|
||||
|
||||
$ ls /etc
|
||||
|
||||
```
|
||||
|
||||
[][8]
|
||||
|
||||
|
||||
|
||||
|
||||
列出工作目录/etc的内容
|
||||
|
||||
|
||||
|
||||
|
||||
3.一个目录总是包含一些隐藏的文件（至少有两个），因此，要展示目录中的所有文件，使用“-a”或“-all”标志:
|
||||
|
||||
|
||||
|
||||
```
|
||||
|
||||
$ ls -a
|
||||
|
||||
```
|
||||
|
||||
[][9]
|
||||
|
||||
|
||||
|
||||
列出工作目录的隐藏文件
|
||||
|
||||
4.你还可以打印输出的每一个文件的详细信息,例如文件权限，链接数，
|
||||
|
||||
所有者名称和组所有者，文件大小，最后修改的时间和文件/目录名称。
|
||||
|
||||
这是由` -l `选项来设置，这意味着一个如下面的屏幕截图般的长长的列表格式
|
||||
|
||||
|
||||
|
||||
```
|
||||
|
||||
$ ls -l
|
||||
|
||||
```
|
||||
|
||||
[][10]
|
||||
|
||||
|
||||
|
||||
长列表目录内容
|
||||
|
||||
###基于日期和基于时刻排序文件
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
5.
|
||||
|
||||
要在目录中列出文件并[对最后修改日期和时间进行排序][11]，在下面的命令中使用“-t”选项:
|
||||
|
||||
|
||||
|
||||
```
|
||||
|
||||
$ ls -lt
|
||||
|
||||
```
|
||||
|
||||
[][12]
|
||||
|
||||
|
||||
|
||||
|
||||
按日期和时间排序ls输出内容
|
||||
|
||||
|
||||
|
||||
6.
|
||||
|
||||
如果你想要一个基于日期和时间的逆向排序文件，你可以使用“-r”选项来工作，像这样：
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
```
|
||||
|
||||
$ ls -ltr
|
||||
|
||||
```
|
||||
|
||||
[][13]
|
||||
|
||||
|
||||
按日期和时间排序的逆向输出
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
我们将在这里结束，但是，有更多的使用信息和选项在[ls命令][14]，
|
||||
|
||||
|
||||
因此，使它成为一个点来看看它或任何其他指南提供[每一个用户应该知道ls的命令技巧][15]或[使用排序命令][16]。
|
||||
|
||||
最后但并非最不重要的，你可以通过以下反馈部分联系我们
|
||||
|
||||
|
||||
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
|
||||
|
||||
via: http://www.tecmint.com/sort-ls-output-by-last-modified-date-and-time
|
||||
|
||||
|
||||
|
||||
作者：[Aaron Kili][a]
|
||||
|
||||
译者：[zky001](https://github.com/zky001)
|
||||
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
|
||||
|
||||
[a]:http://www.tecmint.com/author/aaronkili/
|
||||
|
||||
[1]:http://www.tecmint.com/file-and-directory-management-in-linux/
|
||||
|
||||
[2]:http://www.tecmint.com/15-basic-ls-command-examples-in-linux/
|
||||
|
||||
[3]:http://www.tecmint.com/linux-dir-command-usage-with-examples/
|
||||
|
||||
[4]:http://www.tecmint.com/tag/linux-ls-command/
|
||||
|
||||
[5]:http://www.tecmint.com/sort-command-linux/
|
||||
|
||||
[6]:http://www.tecmint.com/15-basic-ls-command-examples-in-linux/
|
||||
|
||||
[7]:http://www.tecmint.com/wp-content/uploads/2016/10/List-Content-of-Working-Directory.png
|
||||
|
||||
[8]:http://www.tecmint.com/wp-content/uploads/2016/10/List-Contents-of-Directory.png
|
||||
|
||||
[9]:http://www.tecmint.com/wp-content/uploads/2016/10/List-Hidden-Files-in-Directory.png
|
||||
|
||||
[10]:http://www.tecmint.com/wp-content/uploads/2016/10/ls-Long-List-Format.png
|
||||
|
||||
[11]:http://www.tecmint.com/find-and-sort-files-modification-date-and-time-in-linux/
|
||||
|
||||
[12]:http://www.tecmint.com/wp-content/uploads/2016/10/Sort-ls-Output-by-Date-and-Time.png
|
||||
|
||||
[13]:http://www.tecmint.com/wp-content/uploads/2016/10/Sort-ls-Output-Reverse-by-Date-and-Time.png
|
||||
|
||||
[14]:http://www.tecmint.com/tag/linux-ls-command/
|
||||
|
||||
[15]:http://www.tecmint.com/linux-ls-command-tricks/
|
||||
|
||||
[16]:http://www.tecmint.com/linux-sort-command-examples/
|
||||
|
||||
@ -0,0 +1,59 @@
|
||||
OneNewLife translated
|
||||
|
||||
什么时候用 NGINX 来取代 Apache
|
||||
=====
|
||||
|
||||
>两者都是主流的开源网络服务器，但是据 NGINX 的首席执行官 Gus Robertson 所言，他们有不同的使用场景。还有微软呢？他们家的服务器的活跃网站份额在 20 年间首次跌破 10%。
|
||||
|
||||
|
||||
|
||||
Apache 是最受欢迎的网络服务器，不过 NGINX 正迎头直上，而微软的 IIS 几十年来首次跌破 10%。
|
||||
|
||||
[NGINX][4] 已经成为第二大网络服务器。它在很久以前就已经超越了[微软因特网信息服务（IIS）][5]，并且一直在老大 [Apache][6] 的身后穷追不舍。但是，NGINX 的首席执行官在接受采访时表示，Apache 和 NGINX 的用户群体不一样。
|
||||
|
||||
“我认为 Apache 是一个伟大的网络服务器。NGINX 和它的使用场景不同，”Robertson 说。“我们没有把 Apache 当成竞争对手。我们的用户使用 NGINX 来取代硬件负载均衡器和构建微服务，这两个都不是 Apache 的长处。”
|
||||
|
||||
事实上，Robertson 发现许多用户同时使用了两种开源的网络服务。“用户会在 Apache 的上层使用 NGINX 来实现负载均衡。我们的架构是完全不同的，我们可以做更好的并发网络服务。”他还表示 NGINX 在云配置方面的表现更优秀。
|
||||
|
||||
他总结说，“我们是唯一一个仍然在持续增长的网络服务器，其它的网络服务器都在慢慢成为明日黄花。”
|
||||
|
||||
这些增长，加上微软损失的 120 万个活跃站点，导致微软的活跃网站份额下降到 9.27%，这是他们第一次跌破 10%。Apache 的市场份额提高了 0.19%，并继续领跑市场，现在坐拥 46.3% 的活跃站点。尽管如此，多年来 Apache 一直在缓慢下降，而 NGINX 现在上升到了 19%。这不太准确。根据[Netcraft 十月份的网络服务器调查][7]，Apache 当月的活跃网站增加得最多，获得了 180 万个新站点，而 NGINX 增加了 40 万个新站点，增长率排第二。
|
||||
|
||||
NGINX 的开发者正在努力创造他们的开放商业网络服务器 —— [NGINX Plus][8]，通过不断的改进使其变得更有竞争力。NGINX Plus 最新的 [第 11 个发行版（R11）][9]发行了，这个版本更易于扩展和自定义，并支持更广泛的部署。
|
||||
|
||||
这次最大的补充是 [动态模块][10] 的二进制兼容性。这意味着通过 [开源 NGINX 软件][11] 编译的动态模块可以加载到 NGINX Plus。
|
||||
|
||||
这意味着你可以利用大量的 [第三方 NGINX 模块][12] 来扩展 NGINX Plus 的功能，仿照一系列开源和商业化的生产模块。开发者可以基于支持 NGINX Plus 的内核创建自定义扩展、附加组件和新产品。
|
||||
|
||||
NGINX Plus R11 还增强了其它功能：
|
||||
|
||||
* [提升 TCP/UDP 负载均衡][1] —— 新功能包括 SSL 服务器路由、新的日志功能、附加变量以及改进的代理协议支持。这些新功能增强了调试功能，使你能够支持更广泛的企业应用。
|
||||
* [更好的 IP 定位][2] —— 第三方的 GeoIP2 模块现在已经通过认证，并提供给 NGINX Plus 用户。这个新版本提供比原来的 GeoIP 模块更精准和丰富的位置信息。
|
||||
* [增强的 nginScript 模块][3] —— nginScript 是基于 JavaScript 的 NGINX Plus 的下一代配置语言。新功能可以让你在流（TCP/UDP）模块中即时修改请求和响应数据。
|
||||
|
||||
The end result? NGINX is poised to continue to make the race for the top web server a two-horse race. Microsoft IIS? It continues to slowly fade away.
|
||||
最终结果？NGINX 准备继续与 Apache 竞争顶级网络服务器的宝座。至于微软的 IIS？它将逐渐消亡。
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: http://www.zdnet.com/article/when-to-use-nginx-instead-of-apache/
|
||||
|
||||
作者：[ Steven J. Vaughan-Nichols][a]
|
||||
译者：[OneNewLife](https://github.com/OneNewLife)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:http://www.zdnet.com/meet-the-team/us/steven-j-vaughan-nichols/
|
||||
[1]:https://www.nginx.com/blog/nginx-plus-r11-released/?utm_source=nginx-plus-r11-released&utm_medium=blog#r11-tcp-udp-lb
|
||||
[2]:https://www.nginx.com/blog/nginx-plus-r11-released/?utm_source=nginx-plus-r11-released&utm_medium=blog#r11-geoip2
|
||||
[3]:https://www.nginx.com/blog/nginx-plus-r11-released/?utm_source=nginx-plus-r11-released&utm_medium=blog#r11-nginScript
|
||||
[4]:https://www.nginx.com/
|
||||
[5]:https://www.iis.net/
|
||||
[6]:https://httpd.apache.org/
|
||||
[7]:https://news.netcraft.com/archives/2016/10/21/october-2016-web-server-survey.html
|
||||
[8]:https://www.nginx.com/products/
|
||||
[9]:https://www.nginx.com/blog/nginx-plus-r11-released/
|
||||
[10]:https://www.nginx.com/blog/nginx-plus-r11-released/?utm_source=nginx-plus-r11-released&utm_medium=blog#r11-dynamic-modules
|
||||
[11]:https://www.nginx.com/products/download-oss/
|
||||
[12]:https://www.nginx.com/resources/wiki/modules/index.html?utm_source=nginx-plus-r11-released&utm_medium=blog
|
||||
@ -0,0 +1,118 @@
|
||||
# 如何在 Linux 中恢复一个删除了的文件
|
||||
|
||||
你曾经是否遇到这样的事？你意识到你已经通过删除键或者在命令行中使用 ‘rm’ 命令错误的删除了一个不该删除的文件。
|
||||
|
||||
在第一种情况下，你可以到垃圾箱，[搜索文件][6]，然后把它重新存储到它原始的位置。但是第二种情况又该怎么办呢？我想你可能也知道，Linux 命令行不会把被删除的文件放到任何位置，而是直接把它们清除了，于是它们不再存在了。
|
||||
|
||||
在这篇文章里，我将分享一个可能很有帮助的技巧来阻止这件事发生在你身上。同时，我也会分享一个你可能会考虑使用的工具，当你由于过分粗心而删除了某些不该删除的文件时。
|
||||
|
||||
### 为 ’rm -i‘ 创建一个别名
|
||||
|
||||
当 ‘-i' 选项和 rm 命令（也包括其他[文件处理命令比如 cp 或者 mv][5]）同时使用时，在删除文件前会出现一个提示。
|
||||
|
||||
这同样也可以运用到[复制，移动或重命名一个文件][4]，当所在位置已经存在一个和目标文件同名的文件时。
|
||||
|
||||
这个提示给你第二次机会来考虑你是否真的想删除该文件 - 如果你在这个提示上选择确定，那么文件就被删除了。在那种情况下，很抱歉，这个技巧没能保护你远离粗心。
|
||||
|
||||
为了让 rm 成为 ‘rm -i’ 别名，这样做：
|
||||
|
||||
```
|
||||
alias rm='rm -i'
|
||||
|
||||
```
|
||||
|
||||
别名命令将确定 rm 现在已经成为了别名：
|
||||
|
||||
[
|
||||
|
||||
][3]
|
||||
|
||||
增加 rm 别名的命令
|
||||
|
||||
然而，这样做只在当前用户对话的当前 shell 上有效。为了永久改变，你必须像下面展示的这样把它保存到 '~/.bashrc' 中（一些版本的 Linux 系统可能是 '~/.profile'）。
|
||||
|
||||
[
|
||||
|
||||
][2]
|
||||
|
||||
在 Linux 中永久增添别名
|
||||
|
||||
为了让 '~/.bashrc'（或 '~/.profile'）中所做的改变立即生效，从当前 shell 中搜索文件：
|
||||
|
||||
```
|
||||
. ~/.bashr
|
||||
|
||||
```
|
||||
[
|
||||
|
||||
][1]
|
||||
|
||||
在 Linux 中激活别名
|
||||
|
||||
### 取证工具 － Foremost
|
||||
|
||||
但愿你对于你的文件足够小心，只有需要恢复一个来自外部磁盘或 USB 设备的丢失文件时才使用这个工具。
|
||||
|
||||
然而，当你意识到你意外的删除了系统中的一个文件并将要感到恐慌时－不用担心。让我们来看一看 Foremost， 一个被设计用来处理这种状况的取证工具。
|
||||
|
||||
为了在 CentOS/RHEL 7 中安装 Foremost， 你需要首先启用 Repoforge：
|
||||
|
||||
```
|
||||
# rpm -Uvh http://pkgs.repoforge.org/rpmforge-release/rpmforge-release-0.5.3-1.el7.rf.x86_64.rpm
|
||||
# yum install foremost
|
||||
|
||||
```
|
||||
|
||||
然而在 Debian 及其派生系统中，只需这样做：
|
||||
|
||||
```
|
||||
# aptitude install foremost
|
||||
|
||||
```
|
||||
|
||||
安装完成以后，让我们以一个简单的测试开始。我们首先删除 /boot/images 目录下一个名为 'nosdos.jpg' 的图像文件：
|
||||
|
||||
```
|
||||
# cd images
|
||||
# rm nosdos.jpg
|
||||
|
||||
```
|
||||
|
||||
为了恢复这个文件，像下面这样使用 Foremost（你需要首先确认潜在分区 - 在这种情况下， '/boot' 位于 '/dev/sda1' 分区中）
|
||||
|
||||
```
|
||||
# foremost -t jpg -i /dev/sda1 -o /home/gacanepa/rescued
|
||||
|
||||
```
|
||||
|
||||
/home/gacanepa/rescued 是单独磁盘中的一个目录 － 请记住，把文件恢复到被删除文件所在驱动中不是一个明智的做法。
|
||||
|
||||
如果在恢复过程中，占用了被删除文件过去所在的磁盘分区，那么可能没法恢复文件。另外，在进行文件恢复操作前停止所有进程也是至关重要的。
|
||||
|
||||
当 Foremost 执行文件恢复操作完成以后，恢复文件（如果可以恢复）将能够在目录 /home/gacanepa/rescue/jpg 中找到。
|
||||
|
||||
##### 总结
|
||||
|
||||
这篇在文章中，我们阐述了如何避免意外删除一个不该删除的文件以及如何恢复文件如果这样一件不期望的事情发生。然而，警告一下， Foremost 需要花费一段时间运行，时间长短取决于分区的大小。
|
||||
|
||||
一如既往，如果你有什么问题或想法，不要犹豫，让我们知道。请自由使用下面的形式给我们留下一个注记。
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: http://www.tecmint.com/recover-deleted-file-in-linux/
|
||||
|
||||
作者：[ Gabriel Cánepa][a]
|
||||
|
||||
译者：[ucasFL](https://github.com/ucasFL)
|
||||
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:http://www.tecmint.com/author/gacanepa/
|
||||
[1]:http://www.tecmint.com/wp-content/uploads/2016/11/Active-Alias-in-Linux.png
|
||||
[2]:http://www.tecmint.com/wp-content/uploads/2016/11/Add-Alias-Permanently-in-Linux.png
|
||||
[3]:http://www.tecmint.com/wp-content/uploads/2016/11/Add-Alias-rm-Command.png
|
||||
[4]:http://www.tecmint.com/rename-multiple-files-in-linux/
|
||||
[5]:http://www.tecmint.com/progress-monitor-check-progress-of-linux-commands/
|
||||
[6]:http://www.tecmint.com/linux-find-command-to-search-multiple-filenames-extensions/
|
||||
@ -0,0 +1,48 @@
|
||||
[XFCE 桌面新增‘免打扰’模式以及单一应用通知设置的新特性][7]
|
||||
============================================================
|
||||
|
||||
Xfce 的开发者们正忙于把 Xfce 的应用和部件[转移][3]到 GTK3 上，在这个过程中，他们也增加了一些新的特性。
|
||||
|
||||
**"免打扰“**，一个更加被需要的特性，[最近][4]已登陆到了 _xfce-notifyd_ 0.3.4 (Xfce 通知进程)上。
|
||||
|
||||
更近一步地，**最新的 _xfce-notifyd_ 包括一个选项可以在单一应用基础上开启或关闭通知。
|
||||
|
||||
当一个应用发出一个通知以后，这个应用就被加入到到了通知设置的列表里。从通知列表里，你可以控制哪些应用能够显示通知。
|
||||
|
||||
”免打扰“模式和特殊应用通知设置均可在 设置 > 通知 中找到：
|
||||
|
||||
[
|
||||
|
||||
][5]
|
||||
|
||||
|
||||
现在，没有方法可以访问由于启用”免打扰“模式而错过的消息。然而，**通知记录／维持特性被期待在将来会释放。**
|
||||
|
||||
最后， _xfce-notifyd_ 0.3.4 的**另一个特性**是**选择在基本监视器显示通知**（直到现在，通知都是显示在主动监视器）。这个特性目前在 GUI 上是不能用的，必须使用 Xfconf（设置编辑）在 _xfce-notifyd_ 增添一个叫做“／基本监视器”（没有引号）的布尔属性并设置为 "TRUE" 来启用该特性:
|
||||
|
||||
[
|
||||
|
||||
][6]
|
||||
|
||||
**_xfce4-notifyd_ 0.3.4 特性目前在 PPA 上是不可用的，但是不久它可能被增添到[Xfce GTK3][1]中。**
|
||||
|
||||
**如果你想直接从源代码编译，从[这儿][2]下载。**
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: http://www.webupd8.org/2016/11/xfce-gets-do-not-disturb-mode-and-per.html
|
||||
|
||||
作者：[Andrew ][a]
|
||||
译者：[ucasFL](https://github.com/ucasFL)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:http://www.webupd8.org/p/about.html
|
||||
[1]:https://launchpad.net/~xubuntu-dev/+archive/ubuntu/xfce4-gtk3
|
||||
[2]:http://archive.xfce.org/src/apps/xfce4-notifyd/0.3/
|
||||
[3]:https://wiki.xfce.org/releng/4.14/roadmap
|
||||
[4]:http://simon.shimmerproject.org/2016/11/09/xfce4-notifyd-0-3-4-released-do-not-disturb-and-per-application-settings/
|
||||
[5]:https://1.bp.blogspot.com/-fvSesp1ukaQ/WCR8JQVgfiI/AAAAAAAAYl8/IJ1CshVQizs9aG2ClfraVaNjKP3OyxvAgCLcB/s1600/xfce-do-not-disturb.png
|
||||
[6]:https://2.bp.blogspot.com/-M8xZpEHMrq8/WCR9EufvsnI/AAAAAAAAYmA/nLI5JQUtmE0J9TgvNM9ZKGHBdwwBhRH3QCLcB/s1600/xfce-xfconf.png
|
||||
[7]:http://www.webupd8.org/2016/11/xfce-gets-do-not-disturb-mode-and-per.html
|
||||
@ -1,88 +0,0 @@
|
||||
Ubuntu 14.04/16.04 与Windows 10周年版ubuntu Bash性能对比
|
||||
===========================
|
||||
|
||||
今年初，当Microsoft和Canonical发布[Windows 10 Bash 和Ubuntu用户空间][1]，我尝试做了一些初步性能测试 [Ubuntu on Windows 10 对比 原生Ubuntu][2]，这次我发布更多的，关于原生纯净Ubuntu和Base on Windows 10的基准对比。
|
||||
|
||||
|
||||
|
||||
Windows的Linux子系统测试在上周刚刚完成所有测试，并放出升级。 默认的Ubuntu用户空间还是Ubuntu 14.04,但是已经可以升级到16.04。所以测试首先在14.04测试，完成后将系统升级升级到16.04版本并重复所有测试。完成所有基于Windows的测试后，我删除了Ubuntu14.04.5和Ubuntu 16.04 LTS来对比查看性能
|
||||
|
||||
|
||||
|
||||
|
||||
配置为Intel i5 6600K Skylake框架， 16G内存和256东芝ssd， 所有测试都采用原生默认配置。
|
||||
|
||||
|
||||
|
||||
>点击放大查看
|
||||
|
||||
|
||||
这次Ubuntu/Bash on Windows和原生Ubuntu对比测试，采用开源软件Phoronix测试套件，完全自动化并可重复测试。
|
||||
|
||||
|
||||
|
||||
First up was the SQLite embedded database benchmark. The out-of-the-box Ubuntu/Bash on Windows performance was quite slow, but when switching that 14.04 environment to 16.04 LTS, the performance was much faster. However, for this disk-heavy workload the native Ubuntu Linux installations were almost twice as fast as relying upon the Windows Subsystem for Linux.
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
The CompileBench test profile as additional disk-focused workloads show that this is the particular subsystem really straining the Ubuntu performance atop Windows 10 with it being up to multiple times slower.
|
||||
|
||||
Next up were some basic system memory speed tests with Stream.
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
Strangely, the Stream memory benchmarks show better performance with Ubuntu on Windows than Ubuntu itself! This happened on both the 14.04 and 16.04 based environments that the Windows results came out faster.
|
||||
|
||||
Next are more of the CPU-heavy tests,
|
||||
|
||||
|
||||
|
||||
With the Dolfyn scientific test, the performance between Ubuntu on Windows and Ubuntu installed bare metal was actually quite close. With Ubuntu 16.04 the performance is slower on both platforms due to the newer GCC compiler regressing the performance.
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
Fhourstones and John The Ripper show that the performance of Ubuntu running on Windows via the Windows Subsystem for Linux can be incredibly close to the bare metal Ubuntu Linux performance!
|
||||
|
||||
|
||||
|
||||
The x264 results were another strange case similar to Stream where the best performance was actually with Ubuntu on Windows 10 via WSL!
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
The timed compilation benchmarks were heavily in favor of the bare metal Ubuntu Linux installations outside of Windows. This is likely due to these large program compilations requiring plenty of disk reads and from the earlier disk-focused benchmarks showing that is the big area where the Windows Subsystem for Linux is slow.
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
Many of our other common open-source benchmarks show that for the strictly CPU-focused tests, the Windows Subsystem for Linux is close -- or even matches -- the native Ubuntu Linux performance running on the actual hardware.
|
||||
|
||||
These latest Windows Subsystem for Linux results are actually rather impressive. The big letdown is just the continued slow disk/file-system performance, but for CPU-bound workloads the results are very compelling. There's also the rare cases with x264 and Stream where the performance of the Ubuntu user-space on Windows appears to clearly outperform that of Ubuntu Linux running on the hardware by itself.
|
||||
|
||||
Overall the experience was actually quite pleasant and haven't run into any other bugs or annoyances while running with Ubuntu/Bash on Windows. If you're interested in more Windows vs. Linux benchmarks, please consider voicing yourself as a Phoronix Premium subscriber.
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://www.phoronix.com/scan.php?page=article&item=windows10-anv-wsl&num=1
|
||||
|
||||
作者：[Michael Larabel][a]
|
||||
译者：[VicYu/Vic020](http://vicyu.net)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]: http://www.michaellarabel.com/
|
||||
[1]: http://www.phoronix.com/scan.php?page=news_item&px=Ubuntu-User-Space-On-Win10
|
||||
[2]: http://www.phoronix.com/scan.php?page=article&item=windows-10-lxcore&num=1
|
||||
|
||||
Loading…
Reference in New Issue
Block a user