IO Multiplexing

What

• CONCURRENT SERVERS WITHOUT THREADS
• 让用户态 thread 同时对多个 fd 发起监听，调用模式还可以根据使用需要调整为非阻塞、阻塞或超时模式.

How

• select()
• poll()
• epoll()

Why

• Pros: No Lock needed.
• Cons:
  • Blocking System Calls because only one thread is running. Unlike thread based concurrency which can have another thread running while doing Input Output.

Rules

1. No blocking calls are allowed

Links

• NodeJS
• JavaScript Event Loop
• epoll()
• Reactive Programming
• libuv