国庆一家三口分开旅行，各有自己的目的地，我选了舟山，离开上海不远，之前从来没有去过。一人的旅行自然应该惬意为主，打着走到哪算哪的政策主张，也给自己埋下不少的坑。
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Eggjs Boot
#Preface
This article will introduce the boot of Eggjs that is a Node.js web framework.
It is based on Koa and can satisfy your requirement through a large of plugins and middleware, even a your own framework. It is very important to create a cluster, an agent process and some worker processes when it is running. The cluster makes it stronger. Next, we can understand it by reading the source code.
Eggjs has a few major libs, egg-core、egg、egg-cluster、egg-bin、egg-scripts and so on.
egg-core: it extends Koa and is as a parent object of every agent and worker.
egg: it defines some actions for agent and worker, you can almost use these actions to create an app of a single process.
egg-cluster: it creates a cluster and manages them.
egg-scripts and Egg-bin: their job is run the whole app in a different environment.
Tips: We will discuss Eggjs with basing 2.x.x version.
Egg Cluster 简单介绍
如果不清楚什么是Egg.js，希望能移步到它的官网简单看下。另外说它是__约定大于配置__的话，我只能说你真的不了解它，或者说不了解框架，哪个框架没有约定？毕竟没有规矩不成方圆，何况是逻辑性的程序呢？官方列出的特性如下：
1.提供基于 Egg 定制上层框架 的能力
2.高度可扩展的插件机制
3.内置多进程管理
4.基于 Koa 开发，性能优异
5.框架稳定，测试覆盖率高
6.渐进式开发
第1条，它有那么Koa也有啊。第2条，它有，难道Koa、Express等就没有嘛？第4条，更好的补充了Koa不是更好吗？第5条，难道别的框架就不稳定了？第6条，前端鼓吹渐进式、后端也鼓吹，那究竟什么是渐进式呢？
在我看来最吸引我的是第3条，__内置多进程管理__，这个在其它主流nodejs框架中是稀缺的特性，此文就简单聊聊它。