与Redis和Unicorn连接池的好处(Benefits of connection pooling with Redis and Unicorn)

 背景：我有一个Ruby / Rails + Nginx / Unicorn Web应用程序，连接到多个Redis DB（即我没有使用Redis.current ，而是使用全局变量进行不同的连接）。 我知道我需要在创建新的Unicorn worker时在after_fork块中创建一个新连接，如此处和此处所述 。 
 
 我的问题是关于连接池的需求。 根据这个 SO线程， “在Unicorn中，每个进程都建立自己的连接池，所以如果你的数据库池设置是5，你有5个Unicorn工作人员，那么你最多可以有25个连接。但是，因为每个独角兽工作者只能处理一次只有一个连接，那么除非你的应用程序在内部使用线程，否则每个worker只会实际使用一个db连接...池大小大于1意味着每个Unicorn worker都可以访问它不能使用的连接，但它赢了实际上打开连接，这没关系。“ 
 
 由于我不使用Sidekiq，我甚至需要为Redis连接使用连接池吗？ 池大小为1的连接池有什么好处吗？ 或者我应该简单地使用单个连接的变量 - 例如Redis.new（url：ENV [“MY_CACHE”]）？ 

Background: I have a Ruby/Rails + Nginx/Unicorn web app with connections to multiple Redis DBs (i.e. I am not using Redis.current and am instead using global variables for my different connections). I understanding that I need to create a new connection in the after_fork block when a new Unicorn worker is created, as explained here and here.
 
My question is about the need for connection pooling. According to this SO thread, "In Unicorn each process establishes its own connection pool, so you if your db pool setting is 5 and you have 5 Unicorn workers then you can have up to 25 connections. However, since each unicorn worker can handle only one connection at a time, then unless your app uses threading internally each worker will only actually use one db connection... Having a pool size greater than 1 means each Unicorn worker has access to connections it can't use, but it won't actually open the connections, so that doesn't matter."
 
Since I am NOT using Sidekiq, do I even need to use connection pools for my Redis connections? Is there any benefit of a connection pool with a pool size of 1? Or should I simply use variables with single connections -- e.g. Redis.new(url: ENV["MY_CACHE"])?

原文：https://stackoverflow.com/questions/37691120