From 5b5a067713224490d76338bc58d744147a3060f9 Mon Sep 17 00:00:00 2001
From: yanglbme <szuyanglb@outlook.com>
Date: Sat, 5 Jan 2019 20:31:20 +0800
Subject: [PATCH] docs: add hystrix-thread-pool-current-limiting

- Update index.html
- Add hystrix-thread-pool-current-limiting.md
- Update hystrix-introduction and circuit-breaker
---
 README.md                                     |   3 ++-
 .../hystrix-circuit-breaker.md                |   2 +-
 .../high-availability/hystrix-introduction.md |   1 +
 .../hystrix-thread-pool-current-limiting.md   |  19 ++++++++++++++++++
 .../img/bulkhead-partition.jpg                | Bin 0 -> 7057 bytes
 img/bulkhead-partition.jpg                    | Bin 0 -> 7057 bytes
 index.html                                    |   1 +
 7 files changed, 24 insertions(+), 2 deletions(-)
 create mode 100644 docs/high-availability/hystrix-thread-pool-current-limiting.md
 create mode 100644 docs/high-availability/img/bulkhead-partition.jpg
 create mode 100644 img/bulkhead-partition.jpg

diff --git a/README.md b/README.md
index 841b91c..672c34e 100644
--- a/README.md
+++ b/README.md
@@ -67,7 +67,7 @@
 - [如何基于 Dubbo 进行服务治理、服务降级、失败重试以及超时重试？](/docs/distributed-system/dubbo-service-management.md)
 - [分布式服务接口的幂等性如何设计（比如不能重复扣款）？](/docs/distributed-system/distributed-system-idempotency.md)
 - [分布式服务接口请求的顺序性如何保证？](/docs/distributed-system/distributed-system-request-sequence.md)
-- [如何自己设计一个类似 Dubbo 的 rpc 框架？](/docs/distributed-system/dubbo-rpc-design.md)
+- [如何自己设计一个类似 Dubbo 的 RPC 框架？](/docs/distributed-system/dubbo-rpc-design.md)
 
 ### 分布式锁
 - [Zookeeper 都有哪些应用场景？](/docs/distributed-system/zookeeper-application-scenarios.md)
@@ -89,6 +89,7 @@
 - [基于 request cache 请求缓存技术优化批量商品数据查询接口](/docs/high-availability/hystrix-request-cache.md)
 - [基于本地缓存的 fallback 降级机制](/docs/high-availability/hystrix-fallback.md)
 - [深入 Hystrix 断路器执行原理](/docs/high-availability/hystrix-circuit-breaker.md)
+- [深入 Hystrix 线程池隔离与接口限流](/docs/high-availability/hystrix-thread-pool-current-limiting.md)
 
 ### 高可用系统
 - 如何设计一个高可用系统？
diff --git a/docs/high-availability/hystrix-circuit-breaker.md b/docs/high-availability/hystrix-circuit-breaker.md
index f6247e5..5fd28a8 100644
--- a/docs/high-availability/hystrix-circuit-breaker.md
+++ b/docs/high-availability/hystrix-circuit-breaker.md
@@ -172,7 +172,7 @@ ProductInfo(id=1, name=iphone7手机, price=5599.0, pictureList=a.jpg,b.jpg, spe
 
 之后的 9 次请求，都不会执行 run() 方法，也就不会打印以下信息。
 
-```
+```c
 调用接口查询商品数据，productId=-1
 ```
 
diff --git a/docs/high-availability/hystrix-introduction.md b/docs/high-availability/hystrix-introduction.md
index 5497d52..cfe80e2 100644
--- a/docs/high-availability/hystrix-introduction.md
+++ b/docs/high-availability/hystrix-introduction.md
@@ -1,4 +1,5 @@
 ## 用 Hystrix 构建高可用服务架构
+参考 [Hystrix Home](https://github.com/Netflix/Hystrix/wiki#what)。
 
 ### Hystrix 是什么？
 在分布式系统中，每个服务都可能会调用很多其他服务，被调用的那些服务就是**依赖服务**，有的时候某些依赖服务出现故障也是很正常的。
diff --git a/docs/high-availability/hystrix-thread-pool-current-limiting.md b/docs/high-availability/hystrix-thread-pool-current-limiting.md
new file mode 100644
index 0000000..9994821
--- /dev/null
+++ b/docs/high-availability/hystrix-thread-pool-current-limiting.md
@@ -0,0 +1,19 @@
+## 深入 Hystrix 线程池隔离与接口限流
+前面讲了 Hystrix 的 request cache 请求缓存、fallback 优雅降级、circuit breaker 断路器快速熔断，这一讲，我们来详细说说 Hystrix 的线程池隔离与接口限流。
+
+![hystrix-process](/img/hystrix-process.png)
+
+Hystrix 通过判断线程池或者信号量是否已满，超出容量的请求，直接 Reject 走降级，从而达到限流的作用。
+
+限流是限制对后端的服务的访问量，比如说你对 MySQL、Redis、Zookeeper 以及其它各种后端中间件的资源的访问的限制，其实是为了避免过大的流量直接打死后端的服务。
+
+### 线程池隔离技术的设计
+Hystrix 采用了 Bulkhead Partition 舱壁隔离技术，来将外部依赖进行资源隔离，进而避免任何外部依赖的故障导致本服务崩溃。
+
+> **舱壁隔离**，是说将船体内部空间区隔划分成若干个隔舱，一旦某几个隔舱发生破损进水，水流不会在其间相互流动，如此一来船舶在受损时，依然能具有足够的浮力和稳定性，进而减低立即沉船的危险。
+
+![bulkhead-partition](/img/bulkhead-partition.jpg)
+
+Hystrix 对每个外部依赖用一个单独的线程池，这样的话，如果对那个外部依赖调用延迟很严重，最多就是耗尽那个依赖自己的线程池而已，不会影响其他的依赖调用。
+
+### Hystrix 应用线程池机制的场景
diff --git a/docs/high-availability/img/bulkhead-partition.jpg b/docs/high-availability/img/bulkhead-partition.jpg
new file mode 100644
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diff --git a/index.html b/index.html
index 2df609e..ce85ae5 100644
--- a/index.html
+++ b/index.html
@@ -53,6 +53,7 @@
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   <script src="//unpkg.com/prismjs/components/prism-java.min.js"></script>
   <script src="//unpkg.com/prismjs/components/prism-python.min.js"></script>
+  <script src="//unpkg.com/docsify-copy-code"></script>
   <script src="//unpkg.com/docsify/lib/plugins/search.js"></script>
   <script src="//unpkg.com/docsify/lib/plugins/emoji.js"></script>
   <script src="//unpkg.com/docsify/lib/plugins/zoom-image.js"></script>