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published/20201027 Fedora 33 is officially here.md
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[#]: collector: (lujun9972)
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[#]: translator: (wxy)
|
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[#]: reviewer: (wxy)
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[#]: publisher: (wxy)
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||||
[#]: url: (https://linux.cn/article-12764-1.html)
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[#]: subject: (Fedora 33 is officially here!)
|
||||
[#]: via: (https://fedoramagazine.org/announcing-fedora-33/)
|
||||
[#]: author: (Matthew Miller https://fedoramagazine.org/author/mattdm/)
|
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|
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Fedora 33 正式发布了
|
||||
======
|
||||
|
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![][1]
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> 本文译自 Fedora 官方发布公告。
|
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|
||||
今天，我很兴奋地与大家分享数千名 Fedora 项目贡献者辛勤工作的成果：我们的最新版本 Fedora 33 来了! 这是一个有着很多变化的大版本，但我相信所有这些工作也会让您感到舒适，实现我们的目标：即为您带来最新的稳定、强大、健壮的自由和开源软件，并提供许多易于使用的产品。
|
||||
|
||||
如果您不想耽误时间，直接体验，现在就去 <https://getfedora.org/> 下载吧，欲了解详情请继续阅读！
|
||||
|
||||
### 找到适合您的 Fedora 风味！
|
||||
|
||||
Fedora Edition 是针对桌面、服务器和云环境中各种“体现”特定用途的目标产品，现在它也适用于物联网。
|
||||
|
||||
Fedora Workstation 专注于桌面，尤其是面向那些想要“只管去用”的 Linux 操作系统体验的软件开发者。这个版本的特点是 [GNOME 3.38][2]，它一如既往地有很多很棒的改进。新增的 Tour 应用可以帮助新用户学习它们的操作方式。和我们所有其他面向桌面的变体一样，Fedora Workstation 现在使用 [BTRFS 作为默认文件系统][3]。这些发布的版本中带来了很多伟大的增强功能，这个先进的文件系统为之奠定了基础。为了您的视觉享受，Fedora 33 Workstation 现在默认提供了一个动画背景（它会基于一天中的时间变化）。
|
||||
|
||||
Fedora CoreOS 是一个新兴的 Fedora 版本。它是一个自动更新的、最小化的操作系统，用于安全地、大规模地运行容器化工作负载。它提供了几个[更新流][4]，可以遵循大致每两周一次的自动更新。目前 **next** 流是基于 Fedora 33 的，**testing** 和 **stable** 流后继也会跟进。您可以从[下载页面][5]中找到关于跟随 **next** 流发布的工件的信息，并在 [Fedora CoreOS 文档][6]中找到关于如何使用这些工件的信息。
|
||||
|
||||
新晋升为 Edition 状态的 [Fedora IoT][7]，为物联网生态系统和边缘计算用例提供了坚实的基础。在许多功能之外，Fedora 33 IoT 还引入了<ruby>平台抽象安全<rt>Platform AbstRaction for SECurity</rt></ruby>（PARSEC），这是一个开源倡议，以平台无关的方式为硬件安全和加密服务提供了通用 API。
|
||||
|
||||
当然，我们制作的不仅仅是“官方版本”，还有 [Fedora Spin][8]和 [Lab][9]。[Fedora Spin][8] 和 [Lab][9] 针对不同的受众和用例，包括 [Fedora CompNeuro][10]，它为神经科学带来了大量的开源计算建模工具，以及 [KDE Plasma][11] 和 [Xfce][12]等桌面环境。
|
||||
|
||||
此外，别忘了我们还有备用架构：[ARM AArch64、Power 和 S390x][13]。在 Fedora 33 中提供的新功能，AArch64 用户可以使用 .NET Core 语言进行跨平台开发。我们改进了对 Pine64 设备、NVidia Jetson 64 位平台以及 Rockchip 片上系统（SoC）设备的支持，包括 Rock960、RockPro64 和 Rock64。（不过，有个最新的说明：在其中一些设备上可能会出现启动问题。从现有的 Fedora 32 升级是没问题的。更多信息将在[常见错误][14]页面上公布。）
|
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|
||||
我们也很高兴地宣布，Fedora 云镜像和 Fedora CoreOS 将首次与 Fedora 33 一起在亚马逊的 [AWS 市场][15] 中提供。Fedora 云镜像在亚马逊云中已经存在了十多年，您可以通过 AMI ID 或[点击一下][16]来启动我们的官方镜像。该市场提供了获得同样东西的另一种方式，显著扩大了 Fedora 的知名度。这也将使我们的云镜像可以更快地在新的 AWS 区域中可用。特别感谢 David Duncan 让这一切成为现实！
|
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|
||||
### 常规改进
|
||||
|
||||
无论您使用的是哪种版本的 Fedora，您都会得到开源世界提供的最新版本。遵循我们的 [First][17] 原则，我们更新了关键的编程语言和系统库包，包括 Python 3.9、Ruby on Rails 6.0 和 Perl 5.32。在 Fedora KDE 中，我们沿用了 Fedora 32 Workstation 中的工作，默认启用了 EarlyOOM 服务，以改善低内存情况下的用户体验。
|
||||
|
||||
为了让 Fedora 的默认体验更好，我们将 nano 设置为默认编辑器。nano 是一个对新用户友好的编辑器。当然，那些想要像 vi 这样强大的编辑器的用户可以自己设置默认编辑器。
|
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|
||||
我们很高兴您能试用新版本! 前往 <https://getfedora.org/> 并立即下载它。或者如果您已经在运行 Fedora 操作系统，请按照这个简单的[升级说明][18]进行升级。关于 Fedora 33 新特性的更多信息，请参见[发布说明][19]。
|
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|
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### 关于安全启动的说明
|
||||
|
||||
<ruby>安全启动<rt>Secure Boot</rt></ruby>是一种安全标准，它确保只有官方签署的操作系统软件才能加载到您的计算机上。这对于防止持久恶意软件非常重要，因为这些恶意软件可能会隐藏在您的计算机固件中，甚至在重新安装操作系统时也能存活。然而，在 [Boot Hole][20] 漏洞发生后，用于签署 Fedora <ruby>引导加载器<rt>Bootloader</rt></ruby>软件的加密证书将被撤销，并被新的证书取代。由于这将产生大范围的影响，撤销应该要到 2021 年第二季度或更晚才会广泛推行。
|
||||
|
||||
然而，一些用户可能已经从其他操作系统或固件更新中收到了这种撤销。在这种情况下，Fedora 将不能在启用了安全启动时进行安装。要说明的是，这不会影响大多数用户。如果它确实影响到了您，您可以暂时禁用安全启动。我们会在大范围的证书撤销之前发布一个用新证书签署的更新，在所有支持的版本上都可以使用，到那时，安全启动应该可以重新启用。
|
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|
||||
### 万一出现问题时……
|
||||
|
||||
如果您遇到问题，请查看 [Fedora 33 常见错误][14]页面；如果您有疑问，请访问我们的 [Ask Fedora][21] 用户支持平台。
|
||||
|
||||
### 谢谢大家
|
||||
|
||||
感谢在这个发布周期中为 Fedora 项目做出贡献的成千上万的人，尤其是那些在疫情大流行期间为使这个版本准时发布而付出额外努力的人。Fedora 是一个社区，很高兴看到我们如此互相支持。
|
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|
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|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://fedoramagazine.org/announcing-fedora-33/
|
||||
|
||||
作者：[Matthew Miller][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[wxy](https://github.com/wxy)
|
||||
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://fedoramagazine.org/author/mattdm/
|
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[b]: https://github.com/lujun9972
|
||||
[1]: https://fedoramagazine.org/wp-content/uploads/2020/10/f33-final-816x345.jpg
|
||||
[2]: https://www.gnome.org/news/2020/09/gnome-3-38-released/
|
||||
[3]: https://fedoramagazine.org/btrfs-coming-to-fedora-33/
|
||||
[4]: https://docs.fedoraproject.org/en-US/fedora-coreos/update-streams/
|
||||
[5]: https://getfedora.org/en/coreos/download?stream=next
|
||||
[6]: https://docs.fedoraproject.org/en-US/fedora-coreos/getting-started/
|
||||
[7]: https://getfedora.org/iot
|
||||
[8]: https://spins.fedoraproject.org/
|
||||
[9]: https://labs.fedoraproject.org/
|
||||
[10]: https://labs.fedoraproject.org/en/comp-neuro/
|
||||
[11]: https://spins.fedoraproject.org/en/kde/
|
||||
[12]: https://spins.fedoraproject.org/en/xfce/
|
||||
[13]: https://alt.fedoraproject.org/alt/
|
||||
[14]: https://fedoraproject.org/wiki/Common_F33_bugs
|
||||
[15]: https://aws.amazon.com/marketplace
|
||||
[16]: https://getfedora.org/en/coreos/download?tab=cloud_launchable&stream=stable
|
||||
[17]: https://docs.fedoraproject.org/en-US/project/#_first
|
||||
[18]: https://docs.fedoraproject.org/en-US/quick-docs/upgrading/
|
||||
[19]: https://docs.fedoraproject.org/en-US/fedora/f33/release-notes/
|
||||
[20]: https://access.redhat.com/security/vulnerabilities/grub2bootloader
|
||||
[21]: http://ask.fedoraproject.org
|
||||
@ -1,90 +0,0 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: ( )
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
[#]: subject: (Fedora 33 is officially here!)
|
||||
[#]: via: (https://fedoramagazine.org/announcing-fedora-33/)
|
||||
[#]: author: (Matthew Miller https://fedoramagazine.org/author/mattdm/)
|
||||
|
||||
Fedora 33 is officially here!
|
||||
======
|
||||
|
||||
![][1]
|
||||
|
||||
Today, I’m excited to share the results of the hard work of thousands of contributors to the Fedora Project: our latest release, Fedora 33, is here! This is a big release with a lot of change, but I believe all that work will also make it a comfortable one, fulfilling our goal of bringing you the latest stable, powerful, and robust free and open source software in many easy to use offerings.
|
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|
||||
If you just want to get to the bits without delay, head over to <https://getfedora.org/> right now. For details, read on!
|
||||
|
||||
### **Find the Fedora flavor that’s right for you!**
|
||||
|
||||
Fedora Editions are targeted outputs geared toward specific “showcase” uses on the desktop, in server and cloud environments—and now for Internet of Things as well.
|
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|
||||
Fedora Workstation focuses on the desktop, and in particular, it’s geared toward software developers who want a “just works” Linux operating system experience. This release features [GNOME 3.38][2], which has plenty of great improvements as usual. The addition of the Tour application helps new users learn their way around. And like all of our other desktop-oriented variants, Fedora Workstation now uses [BTRFS as the default filesystem][3]. This advanced filesystem lays the foundation for bringing a lot of great enhancements in upcoming releases. For your visual enjoyment, Fedora 33 Workstation now features an animated background (based on time of day) by default.
|
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|
||||
Fedora CoreOS is an emerging Fedora Edition. It’s an automatically-updating, minimal operating system for running containerized workloads securely and at scale. It offers several [update streams][4] that can be followed for automatic updates that occur roughly every two weeks. Currently the **next** stream is based on Fedora 33, with the **testing** and **stable** streams to follow. You can find information about released artifacts that follow the **next** stream from [the download page][5] and information about how to use those artifacts in the [Fedora CoreOS Documentation][6].
|
||||
|
||||
[Fedora IoT][7], newly promoted to Edition status, provides a strong foundation for IoT ecosystems and edge computing use cases. Among many other features, Fedora 33 IoT introduces the Platform AbstRaction for SECurity (PARSEC), an open-source initiative to provide a common API to hardware security and cryptographic services in a platform-agnostic way.
|
||||
|
||||
Of course, we produce more than just the Editions. [Fedora Spins][8] and [Labs][9] target a variety of audiences and use cases, including [Fedora CompNeuro][10], which brings a plethora of open source computational modelling tools for neuroscience, and desktop environments like [KDE Plasma][11] and [Xfce][12].
|
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|
||||
And, don’t forget our alternate architectures: [ARM AArch64, Power, and S390x][13]. New in Fedora 33, AArch64 users can use the .NET Core language for cross-platform development. We have improved support for Pine64 devices, NVidia Jetson 64 bit platforms, and the Rockchip system-on-a-chip devices including the Rock960, RockPro64, and Rock64. (However, a late-breaking note: there may be problems booting on some of these devices. Upgrading from existing Fedora 32 will be fine. More info will be on the [Common Bugs][14] page as we have it.)
|
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|
||||
We’re also excited to announce that the Fedora Cloud Base Image and Fedora CoreOS will be available in Amazon’s [AWS Marketplace][15] for the first time with Fedora 33. Fedora cloud images have been available in the Amazon cloud for over a decade, and you can launch our official images by AMI ID or [with a click][16]. The Marketplace provides an alternate way to get the same thing, with significantly wider visibility for Fedora. This will also make our cloud images available in new AWS regions more quickly. Thank you especially to David Duncan for making this happen!
|
||||
|
||||
### General improvements
|
||||
|
||||
No matter what variant of Fedora you use, you’re getting the latest the open source world has to offer. Following our “[First][17]” foundation, we’ve updated key programming language and system library packages, including Python 3.9, Ruby on Rails 6.0, and Perl 5.32. In Fedora KDE, we’ve followed the work in Fedora 32 Workstation and enabled the EarlyOOM service by default to improve the user experience in low-memory situations.
|
||||
|
||||
To make the default Fedora experience better, we’ve set nano as the default editor. nano is a friendly editor for new users. Those of you who want the power of editors like vi can, of course, set your own default.
|
||||
|
||||
We’re excited for you to try out the new release! Go to <https://getfedora.org/> and download it now. Or if you’re already running a Fedora operating system, follow the easy [upgrade instructions][18]. For more information on the new features in Fedora 33, see the [release notes][19].
|
||||
|
||||
### **A note on Secure Boot**
|
||||
|
||||
Secure Boot is a security standard which ensures that only officially-signed operating system software can load on your computer. This is important for preventing persistent malware which could hide itself in your computer’s firmware and survive even an operating system reinstallation. However, in the wake of the [Boot Hole][20] vulnerability, the cryptographic certificate used to sign Fedora bootloader software will be revoked and replaced with a new one. Because this will have a broad impact, revocation should not happen widely until the second quarter of 2021 or later.
|
||||
|
||||
However, some users may have received this revocation from other operating systems or firmware updates already. In that case, Fedora installations will not boot with Secure Boot enabled. To be clear, this will not affect most users. If it does affect you, you can boot with Secure Boot disabled for the time being. We will release an update signed with the new certificate to be available on all supported releases well before broad-scale certificate revocation takes place, and at that point Secure Boot should be reenabled.
|
||||
|
||||
### **In the unlikely event of a problem….**
|
||||
|
||||
If you run into a problem, check out the [Fedora 33 Common Bugs][14] page, and if you have questions, visit our [Ask Fedora][21] user-support platform.
|
||||
|
||||
### **Thank you everyone**
|
||||
|
||||
Thanks to the thousands of people who contributed to the Fedora Project in this release cycle, and especially to those of you who worked extra hard to make this another on-time release during a pandemic. Fedora is a community, and it’s great to see how much we’ve supported each other.
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://fedoramagazine.org/announcing-fedora-33/
|
||||
|
||||
作者：[Matthew Miller][a]
|
||||
选题：[lujun9972][b]
|
||||
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://fedoramagazine.org/author/mattdm/
|
||||
[b]: https://github.com/lujun9972
|
||||
[1]: https://fedoramagazine.org/wp-content/uploads/2020/10/f33-final-816x345.jpg
|
||||
[2]: https://www.gnome.org/news/2020/09/gnome-3-38-released/
|
||||
[3]: https://fedoramagazine.org/btrfs-coming-to-fedora-33/
|
||||
[4]: https://docs.fedoraproject.org/en-US/fedora-coreos/update-streams/
|
||||
[5]: https://getfedora.org/en/coreos/download?stream=next
|
||||
[6]: https://docs.fedoraproject.org/en-US/fedora-coreos/getting-started/
|
||||
[7]: https://getfedora.org/iot
|
||||
[8]: https://spins.fedoraproject.org/
|
||||
[9]: https://labs.fedoraproject.org/
|
||||
[10]: https://labs.fedoraproject.org/en/comp-neuro/
|
||||
[11]: https://spins.fedoraproject.org/en/kde/
|
||||
[12]: https://spins.fedoraproject.org/en/xfce/
|
||||
[13]: https://alt.fedoraproject.org/alt/
|
||||
[14]: https://fedoraproject.org/wiki/Common_F33_bugs
|
||||
[15]: https://aws.amazon.com/marketplace
|
||||
[16]: https://getfedora.org/en/coreos/download?tab=cloud_launchable&stream=stable
|
||||
[17]: https://docs.fedoraproject.org/en-US/project/#_first
|
||||
[18]: https://docs.fedoraproject.org/en-US/quick-docs/upgrading/
|
||||
[19]: https://docs.fedoraproject.org/en-US/fedora/f33/release-notes/
|
||||
[20]: https://access.redhat.com/security/vulnerabilities/grub2bootloader
|
||||
[21]: http://ask.fedoraproject.org
|
||||
@ -0,0 +1,75 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: ( )
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
[#]: subject: (How to define a product in the open source software supply chain)
|
||||
[#]: via: (https://opensource.com/article/20/10/defining-product-open-source)
|
||||
[#]: author: (Scott McCarty https://opensource.com/users/fatherlinux)
|
||||
|
||||
How to define a product in the open source software supply chain
|
||||
======
|
||||
Differentiation is what makes a product successful. Learn more in part
|
||||
two of this series on open source in the software supply chain.
|
||||
![Gift box opens with colors coming out][1]
|
||||
|
||||
In the first article in this series, "[Is open source a development model, business model, or something else?][2]" I introduced the concept that open source is part of the supply chain for software products. But to truly understand open source as a supply chain, you must have a decent understanding of what a product is. A product can be thought of as a business, and as legendary business guru [Peter Drucker][3] said, "The purpose of business is to create and keep a customer." Drucker's statement means a business or product must be useful enough to pay for, or it will fail. Product differentiation is the thing that creates and retains customers.
|
||||
|
||||
### What's in a software product?
|
||||
|
||||
Even in the stone age of 1999, when I started my career, the concept of software products existed—you could go to a store and purchase boxed copies of Red Hat Linux on compact discs (though floppies were still very much in use). The idea of software products existing might sound like a joke, and it is, but in the 1940s and 1950s (when computers, as we know them, were created), software was not a component of value that was bought and sold. There was no market for software. You couldn't buy it, sell it, or access it online.
|
||||
|
||||
Instead of buying software, the choice was to build or buy a physical computer; with either option, you wrote the software yourself for that specific computer.
|
||||
|
||||
> _That… specific… computer…_
|
||||
|
||||
No joke. In the early days of computers, software couldn't run anywhere except for the computer you wrote it on. In fact, in the early days, you couldn't even use the same programming language on two different computers. But, as computers evolved, system software, such as operating systems, assemblers, and compilers, were created. And with the advent of this system software, application code became more reusable and portable.
|
||||
|
||||
In the 1960s, cross-platform compilers and operating systems led to the concept of reusable code, such as macros and eventually libraries. At the beginning of every project, you built your own reusable functions and libraries. (Computer science courses still force you to do this so that you learn what's going on behind the scenes.) Concurrently, processors and operating systems standardized, enabling portability between computers.
|
||||
|
||||
In the early days, these components were used within single organizations (e.g., a government, university, company, etc.), but the desire to share software among organizations emerged quickly. If you're interested in understanding the history of code portability from the first computers to containers, see "Fatherlinux's" [Container portability][4] series or the [History of compiler construction][5] Wikipedia page. Suffice to say, code had to be portable before anyone could have software products, open source or even containers.
|
||||
|
||||
### Reusable and portable software
|
||||
|
||||
Once code became portable and shareable between organizations, the next logical step was to sell it. In these early days, having software that did _something useful_ was differentiating in the marketplace. This was a breakthrough because if you needed a calculator, a compiler, or a piece of word processing software, it became cheaper and easier to buy it than to write it. So software products were born.
|
||||
|
||||
This model really only worked to tackle general-purpose problems that a lot of people share—things like calculating numbers, writing documents, or compiling software; these are business problems. General-purpose software is great, but it doesn't elegantly solve specific problems related to business rules within a single industry or organization, although you can abuse Excel or Google Sheets pretty hard. For specific business problems, it's more efficient to write custom code. This need led to the rise of middleware, things like Java, service buses, and databases. Middleware was bought and sold to assist with custom software development.
|
||||
|
||||
Code portability led to a marketplace for software applications and middleware. Software companies began to provide competing solutions with differentiated value. You picked the compiler or the calculator that you wanted based on features. The existence of competing solutions was great for consumers because it drove software companies to create more specialized solutions, each with unique value. Whether a product is built on open source or not, it must provide unique value in the marketplace.
|
||||
|
||||
### Understanding differentiated value
|
||||
|
||||
To explain differentiated value, I'll use an analogy about automobiles. Families need cars, sport utility vehicles (SUVs), or minivans. They might want comfortable seats, infotainment systems, or safety features. They often have a preference on color. Each family is different and has specific needs, so the perfect automobile would be one that the family built together as a project.
|
||||
|
||||
Most families don't have the time, desire, money, or credit to buy all of the components necessary to build the perfect car from scratch, much less the time to maintain it over a given lifecycle. It wouldn't be an economical investment of time or money for a family. It would cost them way more, and take a long time to build. Instead, families buy automobiles from existing vendors, as a built solution to their transportation problem. Although the bought car will be imperfect, it will approximately meet their needs with much less time and money invested.
|
||||
|
||||
Automobile vendors put a solution together with undifferentiated and differentiated components. This includes everything from the motor, fuel injectors, tires, and seats in the car, to the buying experience at the dealership, the financing, and the service program while the car is owned. All of these features and experiences are a component of the solution that families buy when looking for an automobile. The combination of all these things is what produces something that is different and, hopefully, better in the marketplace. We call this _differentiation_. The more competing solutions, the more differentiation in the marketplace, and the better the chance that a family can find a car that matches their needs more approximately.
|
||||
|
||||
### Differentiation in open source
|
||||
|
||||
In a traditional manufactured product or service, there is a distinction between the value provided by the supplier and the value provided by the company selling directly to the consumer. You could make a further distinction between business-to-consumer (B2C) or business-to-business (B2B) products and services, but that's beyond the scope of this series.
|
||||
|
||||
The astute reader may already be thinking, "yeah, but with traditional products, the suppliers are also companies selling products with differentiation." This is completely true, and in this way, open source projects are no different. Community-driven, open source projects don't have the advantage of expensive marketing campaigns, focus groups, and sales teams to educate customers, but they must also differentiate themselves in the marketplace.
|
||||
|
||||
Differentiation is an important concept for product managers, developers, and even systems administrators. Even in a broader context, the output of any sort of knowledge work—code, writing, music, or art—differentiation is what brings value and meaning to our work. Differentiation is what creates value, whether it's a software product or service, labor, or even music.
|
||||
|
||||
In the next article, I'll dive deeper into how software product teams differentiate their solutions from the open source components provided by their suppliers. We'll even cover software as a service (SaaS).
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://opensource.com/article/20/10/defining-product-open-source
|
||||
|
||||
作者：[Scott McCarty][a]
|
||||
选题：[lujun9972][b]
|
||||
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/fatherlinux
|
||||
[b]: https://github.com/lujun9972
|
||||
[1]: https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/OSDC_gift_giveaway_box_520x292.png?itok=w1YQhNH1 (Gift box opens with colors coming out)
|
||||
[2]: https://opensource.com/article/20/10/open-source-supply-chain
|
||||
[3]: https://en.wikipedia.org/wiki/Peter_Drucker
|
||||
[4]: http://crunchtools.com/container-portability-part-1/
|
||||
[5]: https://en.wikipedia.org/wiki/History_of_compiler_construction
|
||||
@ -1,89 +0,0 @@
|
||||
[#]: collector: "lujun9972"
|
||||
[#]: translator: "xiao-song-123"
|
||||
[#]: reviewer: " "
|
||||
[#]: publisher: " "
|
||||
[#]: url: " "
|
||||
[#]: subject: "How open source underpins blockchain technology"
|
||||
[#]: via: "https://opensource.com/article/20/10/open-source-blockchain"
|
||||
[#]: author: "Matt Shealy https://opensource.com/users/mshealy"
|
||||
|
||||
How open source underpins blockchain technology
|
||||
======
|
||||
Openness, not regulation, is what creates blockchain's security and
|
||||
reliability.
|
||||
![cubes coming together to create a larger cube][1]
|
||||
|
||||
People are often surprised when they find out that blockchain technology, which is known for its security, is built on open source software code. In fact, this openness is what creates its security and reliability.
|
||||
|
||||
One of the core values of building anything as open source is gaining efficiency. Creating a community of developers with different perspectives and skillsets, all working on the same code base, can exponentially increase the number and complexity of applications built.
|
||||
|
||||
### Open source: more common than people think
|
||||
|
||||
One of the more popular operating systems, Linux, is open source. Linux powers the servers for many of the services we feel comfortable sharing personal information on every day. This includes Google, Facebook, and thousands of major websites. When you're interacting with these services, you're doing so on computer networks that are running Linux. Chromebooks are using Linux. Android phones use an operating system based on Linux.
|
||||
|
||||
Linux is not owned by a corporation. It's free to use and created by collaborative efforts. More than 20,000 developers from more than 1,700 companies [have contributed to the code][2] since its origins in 2005.
|
||||
|
||||
That's how open source software works. Tons of people contribute and constantly add, modify, or build off the open source codebase to create new apps and platforms. Much of the software code for blockchain and cryptocurrency has been developed using open source software. Open source software is built by passionate users that are constantly on guard for bugs, glitches, or flaws. When a problem is discovered, a community of developers works separately and together on the fix.
|
||||
|
||||
### Blockchain and open source
|
||||
|
||||
An entire community of open source blockchain developers is constantly adding to and refining the codebase.
|
||||
|
||||
Here are the fundamental ways blockchain performs:
|
||||
|
||||
* Blockchain platforms have a transactional database that allows peers to transact with each other at any time.
|
||||
* User-identification labels are attached that facilitate the transactions.
|
||||
* The platforms must have a secure way to verify transactions before they become approved.
|
||||
* Transactions that cannot be verified will not take place.
|
||||
|
||||
|
||||
|
||||
Open source software allows developers to create these platforms in a [decentralized application (Dapp)][3], which is key to the safety, security, and variability of transactions in the blockchain.
|
||||
|
||||
This decentralized approach means there is no central authority to mediate transactions. That means no one person controls what happens. Direct peer-to-peer interactions can happen quickly and securely. As transactions are recorded in the ledger, they are distributed across the ecosystem.
|
||||
|
||||
Blockchain uses cryptography to keep things secure. Each transaction carries information connecting it with previous transactions to verify its authenticity. This prevents threat actors from tampering with the data because once it's added to the public ledger, it can't be changed by other users.
|
||||
|
||||
### Is blockchain open source?
|
||||
|
||||
Although blockchain itself may not technically be open source, blockchain _systems_ are typically implemented with open source software using a concept that embodies an open culture because no government authority regulates it. Proprietary software developed by a private company to handle financial transactions is likely regulated by [government agencies][4]. In the US, that might include the Securities and Exchange Commission (SEC), the Federal Reserve Board, and the Federal Deposit Insurance Corporation (FDIC). Blockchain technology doesn't require government oversight when it's used in an open environment. In effect, the community of users is what verifies transactions.
|
||||
|
||||
You might call it an extreme form of crowdsourcing, both for developing the open source software that's used to build the blockchain platforms and for verifying transactions. That's one of the reasons blockchain has gotten so much attention: It has the potential to disrupt entire industries because it acts as an authoritative intermediary to handle and verify transactions.
|
||||
|
||||
### Bitcoin, Ethereum, and other cryptocurrencies
|
||||
|
||||
As of June 2020, more than [50 million people have blockchain wallets][5]. Most are used for financial transactions, such as trading Bitcoin, Ethereum, and other cryptocurrencies. It's become mainstream for many to [check cryptocurrency prices][6] the same way traders watch stock prices.
|
||||
|
||||
Cryptocurrency platforms also use open source software. The [Ethereum project][7] developed free and open source software that anyone can use, and a large community of developers contributes to the code. The Bitcoin reference client was developed by more than 450 developers and engineers that have made more than 150,000 contributions to the code-writing effort.
|
||||
|
||||
A cryptocurrency blockchain is a continuously growing record. Each record is linked together in a sequence, and the records are called blocks. When linked together, they form a chain. Each block has its own [unique marker called a hash][8]. A block contains its hash and a cryptographic hash from a previous block. In essence, each block is linked to the previous block, forming long chains that are impossible to break, with each containing information about other blocks that are used to verify transactions.
|
||||
|
||||
There's no central bank in financial or cryptocurrency blockchains. The blocks are distributed throughout the internet, creating a robust audit trail that can be tracked. Anyone with access to the chain can verify a transaction but cannot change the records.
|
||||
|
||||
### An unbreakable chain
|
||||
|
||||
While blockchains are not regulated by any government or agency, the distributed network keeps them secure. As chains grow, each transaction makes it more difficult to fake. Blocks are distributed all over the world in networks using trust markers that can't be changed. The chain becomes virtually unbreakable.
|
||||
|
||||
The code behind this decentralized network is open source and is one of the reasons users trust each other in transactions rather than having to use an intermediary such as a bank or broker. The software underpinning cryptocurrency platforms is open to anyone and free to use, created by consortiums of developers that are independent of each other. This has created one of the world's largest check-and-balance systems.
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://opensource.com/article/20/10/open-source-blockchain
|
||||
|
||||
作者：[Matt Shealy][a]
|
||||
选题：[lujun9972][b]
|
||||
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/mshealy
|
||||
[b]: https://github.com/lujun9972
|
||||
[1]: https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/cube_innovation_process_block_container.png?itok=vkPYmSRQ "cubes coming together to create a larger cube"
|
||||
[2]: https://www.linuxfoundation.org/wp-content/uploads/2020/08/2020_kernel_history_report_082720.pdf
|
||||
[3]: https://www.freecodecamp.org/news/what-is-a-dapp-a-guide-to-ethereum-dapps/
|
||||
[4]: https://www.investopedia.com/ask/answers/063015/what-are-some-major-regulatory-agencies-responsible-overseeing-financial-institutions-us.asp
|
||||
[5]: https://www.statista.com/statistics/647374/worldwide-blockchain-wallet-users/
|
||||
[6]: https://www.okex.com/markets
|
||||
[7]: https://ethereum.org/en/
|
||||
[8]: https://opensource.com/article/18/7/bitcoin-blockchain-and-open-source
|
||||
@ -1,63 +0,0 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: (geekpi)
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
[#]: subject: (Start using virtual tables in Apache Cassandra 4.0)
|
||||
[#]: via: (https://opensource.com/article/20/10/virtual-tables-apache-cassandra)
|
||||
[#]: author: (Ben Bromhead https://opensource.com/users/ben-bromhead)
|
||||
|
||||
Start using virtual tables in Apache Cassandra 4.0
|
||||
======
|
||||
What they are and how to use them.
|
||||
![Computer laptop in space][1]
|
||||
|
||||
Among the [many additions][2] in the recent [Apache Cassandra 4.0 beta release][3], virtual tables is one that deserves some attention.
|
||||
|
||||
In previous versions of Cassandra, users needed access to Java Management Extensions ([JMX][4]) to examine Cassandra details such as running compactions, clients, metrics, and a variety of configuration settings. Virtual tables removes these challenges. Cassandra 4.0 beta enables users to query those details and data as Cassandra Query Language (CQL) rows from a read-only system table.
|
||||
|
||||
Here is how the JMX-based mechanism in previous Cassandra versions worked. Imagine a user wants to check on the compaction status of a particular node in a cluster. The user first has to establish a JMX connection to run `nodetool compactionstats` on the node. This requirement immediately presents the user with a few complications. Is the user's client configured for JMX access? Are the Cassandra nodes and firewall configured to allow JMX access? Are the proper measures for security and auditing prepared and in place? These are only some of the concerns users had to contend with when dealing with in previous versions of Cassandra.
|
||||
|
||||
With Cassandra 4.0, virtual tables make it possible for users to query the information they need by utilizing their previously configured driver. This change removes all overhead associated with implementing and maintaining JMX access.
|
||||
|
||||
Cassandra 4.0 creates two new keyspaces to help users leverage virtual tables: `system_views` and `system_virtual_schema`. The `system_views` keyspace contains all the valuable information that users seek, usefully stored in a number of tables. The `system_virtual_schema` keyspace, as the name implies, stores all necessary schema information for those virtual tables.
|
||||
|
||||
![system_views and system_virtual_schema keyspaces and tables][5]
|
||||
|
||||
(Ben Bromhead, [CC BY-SA 4.0][6])
|
||||
|
||||
It's important to understand that the scope of each virtual table is restricted to its node. Any query of virtual tables will return data that is valid only for the node that acts as its coordinator, regardless of consistency. To simplify for this requirement, support has been added to several drivers to specify the coordinator node in these queries (the Python, DataStax Java, and other drivers now offer this support).
|
||||
|
||||
To illustrate, examine this `sstable_tasks` virtual table. This virtual table displays all operations on [SSTables][7], including compactions, cleanups, upgrades, and more.
|
||||
|
||||
![Querying the sstable_tasks virtual table][8]
|
||||
|
||||
(Ben Bromhead, [CC BY-SA 4.0][6])
|
||||
|
||||
If a user were to run `nodetool compactionstats` in a previous Cassandra version, this is the same type of information that would be displayed. Here, the query finds that the node currently has one active compaction. It also displays its progress and its keyspace and table. Thanks to the virtual table, a user can gather this information quickly, and just as efficiently gain the insight needed to correctly diagnose the cluster's health.
|
||||
|
||||
To be clear, Cassandra 4.0 doesn't eliminate the need for JMX access: JMX is still the only option for querying some metrics. That said, users will welcome the ability to pull key cluster metrics simply by using CQL. Thanks to the convenience afforded by virtual tables, users may be able to reinvest time and resources previously devoted to JMX tools into Cassandra itself. Client-side tooling should also begin to leverage the advantages offered by virtual tables.
|
||||
|
||||
If you are interested in the Cassandra 4.0 beta release and its virtual tables feature, [try it out][3].
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://opensource.com/article/20/10/virtual-tables-apache-cassandra
|
||||
|
||||
作者：[Ben Bromhead][a]
|
||||
选题：[lujun9972][b]
|
||||
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/ben-bromhead
|
||||
[b]: https://github.com/lujun9972
|
||||
[1]: https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/computer_space_graphic_cosmic.png?itok=wu493YbB (Computer laptop in space)
|
||||
[2]: https://www.instaclustr.com/apache-cassandra-4-0-beta-released/
|
||||
[3]: https://cassandra.apache.org/download/
|
||||
[4]: https://en.wikipedia.org/wiki/Java_Management_Extensions
|
||||
[5]: https://opensource.com/sites/default/files/uploads/cassandra_virtual-tables.png (system_views and system_virtual_schema keyspaces and tables)
|
||||
[6]: https://creativecommons.org/licenses/by-sa/4.0/
|
||||
[7]: https://cassandra.apache.org/doc/latest/architecture/storage_engine.html#sstables
|
||||
[8]: https://opensource.com/sites/default/files/uploads/cassandra_virtual-tables_sstable_tasks.png (Querying the sstable_tasks virtual table)
|
||||
@ -1,5 +1,5 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: ( )
|
||||
[#]: translator: (geekpi)
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
|
||||
@ -0,0 +1,90 @@
|
||||
[#]: collector: "lujun9972"
|
||||
[#]: translator: "xiao-song-123"
|
||||
[#]: reviewer: " "
|
||||
[#]: publisher: " "
|
||||
[#]: url: " "
|
||||
[#]: subject: "How open source underpins blockchain technology"
|
||||
[#]: via: "https://opensource.com/article/20/10/open-source-blockchain"
|
||||
[#]: author: "Matt Shealy https://opensource.com/users/mshealy"
|
||||
|
||||
开源是如何支撑区块链技术发展的
|
||||
======
|
||||
创造出区块链安全性和可靠性的原因：是开放，而非监管。
|
||||
|
||||
![cubes coming together to create a larger cube][1]
|
||||
|
||||
|
||||
当人们发现以安全性而闻名的区块链技术居然是建立在开源软件代码之上时，通常会感到非常惊讶。事实上，正是这种开放性才赋予了区块链技术的安全性和可靠性。
|
||||
|
||||
把任何事物构建成开源的，其核心价值之一就是提高效率。建立起一个有着不同观点和技能的开发人员社区，这些开发人员工作在同一个代码库的时候，可以成倍增加构建出来的应用程序数量以及复杂性。
|
||||
|
||||
### 开源比人们想象中的要更加普遍
|
||||
|
||||
开源的 Linux，就是一种比较流行的操作系统。Linux 为服务器提供了许多服务，这些服务让我们可以轻松地共享个人信息。其中包括 Google，Facebook 和数千个主要网站。当我们使用这些服务时，就是在和这些在网络上运行着 Linux 系统的计算机进行交互。Chromebook 也使用 Linux，Android 手机使用的操作系统也是基于 Linux 的。
|
||||
|
||||
Linux 不属于任何一家公司，人们可以免费使用并且可以共同协作来完善创造它。自 2005 年推出以来，已经有来自 1,700 多家公司的 20,000 多名开发人员 [为其中的代码做出了贡献][2] 。
|
||||
|
||||
这就是开源软件的工作原理。大量的人为此贡献，并不断添加、修改或构建开源代码库来创建新的应用程序和平台。区块链和加密货币的大部分代码都是使用开源软件开发的。开源软件是由热情的用户构建的，这些用户对错误、故障或缺陷时刻保持警惕。当发现问题时，开源社区中的开发人员将一起努力来解决问题。
|
||||
|
||||
### 区块链和开源
|
||||
|
||||
整个开源区块链开发者社区都在不断地添加和完善代码库。
|
||||
|
||||
以下是区块链执行的基本方式：
|
||||
|
||||
* 区块链平台具有一个交易数据库，该交易数据库允许对等方在任何时候彼此进行交易。
|
||||
* 附有用户识别标签，以方便交易。
|
||||
* 平台一定有一种安全的方式来在交易批准前对交易进行验证。
|
||||
* 无法被验证的交易不会进行。
|
||||
|
||||
|
||||
|
||||
开源软件允许开发者在 [去中心化应用程序（Dapp）][3]中创建这些平台，这是区块链中交易的安全性、安全性和可变性的关键。
|
||||
|
||||
这种去中心化的方式意味着没有中央权威机构来调解交易，没有人能控制发生的事情。直接点对点的交易可以更快速、安全的进行。随着交易记录在分类账簿中，这条交易记录也会分发到系统各处。
|
||||
|
||||
区块链使用密码学来保证安全。每一笔交易都携带着与前一笔交易相关联的信息，以验证其真实性。这可以防止威胁者篡改数据，因为一旦数据被添加到公共分类账中，其他用户就不能更改。
|
||||
|
||||
### 区块链是开源的吗？
|
||||
|
||||
虽然区块链本身在技术上可能不是开源的，但区块链系统通常是使用开源软件实现的，因为没有政府机构对其进行监管，所以这些开源软件使用的概念体现了一种开放文化。私人公司开发的用于处理金融交易的专有软件很可能受到 [政府机构 ][4] 的监管。在美国，这可能包括美国证券交易委员会 (SEC)、联邦储备委员会和联邦存款保险公司 (FDIC)。区块链技术在开放环境下使用不需要政府监管，实际上，用来验证交易的是用户社区。
|
||||
|
||||
你可以称它为众包的一种极端形式，既用于开发构建区块链平台的开源软件，也用于验证交易。这就是区块链得到如此多关注的原因之一：它有可能颠覆整个行业，因为它可以作为处理和验证交易的权威中介。
|
||||
|
||||
### 比特币，以太坊和其他加密货币
|
||||
|
||||
截至2020年6月，超过 [5000万人拥有区块链钱包][5] 。他们大多数用于金融交易，例如交易比特币，以太坊和其他加密货币。 与交易员观察股票价格一样，[检查加密货币价格][6] 已成为许多人的主流。
|
||||
|
||||
加密货币平台也使用开源软件。[以太坊项目][7] 开发出了任何人都可以免费使用的开源软件，社区中大量的开发者都为此贡献了代码。比特币客户端的参考实现版是由 450 多个开发人员和工程师进行开发的，他们已经贡献了超过 150,000 行代码。
|
||||
|
||||
加密货币区块链是一个持续增长的记录。每个被称作为块的记录按顺序链接在一起，它们互相链接形成一条链。每个块都有其自己的唯一标记，这个标记称为 [哈希][8] 。一个块包含自身的哈希值和前一个块密码的哈希值。从本质上讲，每个块都链接到前一个块，形成了无法中断的长链，每个长链都包含有关用于验证交易的其他块的信息。
|
||||
|
||||
在金融或是加密货币的区块链中没有中央银行。这些分布在整个互联网中的区块，建立了一个性能强大的审计跟踪系统。任何人都能够通过区块链来验证交易，但却不能更改上面的记录。
|
||||
|
||||
### 牢不可破的区块链
|
||||
|
||||
尽管区块链不受任何政府或机构的监管，但分布式的网络保证了它们的安全。随着区块链的发展，每一笔交易都会增加伪造的难度。区块分布在世界各地的网络中，它们使用的信任标记不可被改变，这条链条变得牢不可破。
|
||||
|
||||
这种去中心化的网络，其背后的代码是开源的，也是用户在交易中不必使用诸如银行或经纪人之类的中介就可以相互信任的原因之一。支撑加密货币平台的软件是由相互独立的开发者组建的联盟创建的，并且任何人都可以免费使用。这创造了世界上最大的制衡体系之一。
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://opensource.com/article/20/10/open-source-blockchain
|
||||
|
||||
作者：[Matt Shealy][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[xiao-song-123](https://github.com/xiao-song-123)
|
||||
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/mshealy
|
||||
[b]: https://github.com/lujun9972
|
||||
[1]: https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/cube_innovation_process_block_container.png?itok=vkPYmSRQ "cubes coming together to create a larger cube"
|
||||
[2]: https://www.linuxfoundation.org/wp-content/uploads/2020/08/2020_kernel_history_report_082720.pdf
|
||||
[3]: https://www.freecodecamp.org/news/what-is-a-dapp-a-guide-to-ethereum-dapps/
|
||||
[4]: https://www.investopedia.com/ask/answers/063015/what-are-some-major-regulatory-agencies-responsible-overseeing-financial-institutions-us.asp
|
||||
[5]: https://www.statista.com/statistics/647374/worldwide-blockchain-wallet-users/
|
||||
[6]: https://www.okex.com/markets
|
||||
[7]: https://ethereum.org/en/
|
||||
[8]: https://opensource.com/article/18/7/bitcoin-blockchain-and-open-source
|
||||
@ -0,0 +1,63 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: (geekpi)
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
[#]: subject: (Start using virtual tables in Apache Cassandra 4.0)
|
||||
[#]: via: (https://opensource.com/article/20/10/virtual-tables-apache-cassandra)
|
||||
[#]: author: (Ben Bromhead https://opensource.com/users/ben-bromhead)
|
||||
|
||||
开始在 Apache Cassandra 4.0 中使用虚拟表
|
||||
======
|
||||
它们是什么以及如何使用它们。
|
||||
![Computer laptop in space][1]
|
||||
|
||||
在最近的 [Apache Cassandra 4.0 测试版][3]中的[众多新增功能][2]中，虚拟表是一个值得关注的功能。
|
||||
|
||||
在以前的 Cassandra 版本中，用户需要访问 Java 管理扩展 （[JMX][4]） 来检查 Cassandra 的细节，如运行中的压缩、客户端、度量和各种配置设置。虚拟表消除了这些挑战。Cassandra 4.0 测试版使用户能够从一个只读的系统表中以 Cassandra 查询语言 （CQL） 行的形式查询这些细节和数据。
|
||||
|
||||
以下是之前 Cassandra 版本中基于 JMX 的机制是如何工作的。想象一下，一个用户想要检查集群中某个节点的压缩状态。用户首先要建立一个 JMX 连接，在节点上运行 `nodetool compactionstats`。这个要求给用户带来了一些复杂的问题。用户的客户端是否配置了 JMX 访问？Cassandra 节点和防火墙是否配置为允许 JMX 访问？是否准备好了适当的安全和审计措施，并落实到位？这些只是用户在处理 Cassandra 以前版本时不得不面对的一些问题。
|
||||
|
||||
在 Cassandra 4.0 中，虚拟表使得用户可以利用之前配置的驱动来查询所需信息。这一变化消除了与实现和维护 JMX 访问相关的所有开销。
|
||||
|
||||
Cassandra 4.0 创建了两个新的键空间来帮助用户利用虚拟表：`system_views` 和 `system_virtual_schema`。`system_views` 键空间包含了用户查询的所有有价值的信息，有用地存储在一些表中。`system_virtual_schema` 键空间，顾名思义，存储了这些虚拟表的所有必要的模式信息。
|
||||
|
||||
![system_views and system_virtual_schema keyspaces and tables][5]
|
||||
|
||||
(Ben Bromhead, [CC BY-SA 4.0][6])
|
||||
|
||||
重要的是要明白，每个虚拟表的范围仅限于其节点。任何虚拟表查询都将返回只对作为其协调器的节点有效的数据，而不管一致性如何。为了简化这一要求，已经在几个驱动中添加了支持，以便在这些查询中指定协调器节点 （Python、DataStax Java 和其他驱动现在提供了这种支持）。
|
||||
|
||||
为了说明这一点，请检查这个 `sstable_tasks` 虚拟表。这个虚拟表显示了对 [SSTables][7] 的所有操作，包括压缩、清理、升级等。
|
||||
|
||||
![Querying the sstable_tasks virtual table][8]
|
||||
|
||||
(Ben Bromhead, [CC BY-SA 4.0][6])
|
||||
|
||||
如果用户在以前的 Cassandra 版本中运行 `nodetool compactionstats`，则会显示相同类型的信息。 在这里，查询发现该节点当前有一个活动的压缩。它还显示了它的进度以及它的键空间和表。得益于虚拟表，用户可以快速收集这些信息，并同样有效地获得正确诊断集群健康状况所需的能力。
|
||||
|
||||
需要说明的是，Cassandra 4.0 并没有去除对 JMX 访问的需求。JMX 仍然是查询某些指标的唯一选择。尽管如此，用户会欢迎简单地使用 CQL 来获取关键集群指标的能力。由于虚拟表提供的便利，用户可能会将之前投入到 JMX 工具的时间和资源重新投入到 Cassandra 本身。客户端工具也应该开始利用虚拟表提供的优势。
|
||||
|
||||
如果你对 Cassandra 4.0 测试版及其虚拟表功能感兴趣，请[试试试它][3]。
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://opensource.com/article/20/10/virtual-tables-apache-cassandra
|
||||
|
||||
作者：[Ben Bromhead][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[geekpi](https://github.com/geekpi)
|
||||
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/ben-bromhead
|
||||
[b]: https://github.com/lujun9972
|
||||
[1]: https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/computer_space_graphic_cosmic.png?itok=wu493YbB (Computer laptop in space)
|
||||
[2]: https://www.instaclustr.com/apache-cassandra-4-0-beta-released/
|
||||
[3]: https://cassandra.apache.org/download/
|
||||
[4]: https://en.wikipedia.org/wiki/Java_Management_Extensions
|
||||
[5]: https://opensource.com/sites/default/files/uploads/cassandra_virtual-tables.png (system_views and system_virtual_schema keyspaces and tables)
|
||||
[6]: https://creativecommons.org/licenses/by-sa/4.0/
|
||||
[7]: https://cassandra.apache.org/doc/latest/architecture/storage_engine.html#sstables
|
||||
[8]: https://opensource.com/sites/default/files/uploads/cassandra_virtual-tables_sstable_tasks.png (Querying the sstable_tasks virtual table)
|
||||
Loading…
Reference in New Issue
Block a user