Before Tomcat EndPoint: I/O Models

When an user thread launchs an I/O operation, it would have to experience two steps to get the network data.

• The user thread wait for the OS kernel copy the data from the network interface to the kernel space.
• The OS kernel copy the data from the kernel space to the user space.

To complete the two steps, smart people proposed some I/O models. Follow these models, we can get the data from network.

There are five I/O models in Unix: blocking I/O, nonblocking I/O, I/O multiplexing (select and poll), signal driven I/O (SIGIO), asynchronous I/O (the POSIX aio_functions).

Blocking I/O Model

Nonblocking I/O Model

I/O Multiplexing Model

Signal-Driven I/O Model

Asynchronous I/O Model

Before Tomcat EndPoint: I/O Models

原文：https://www.cnblogs.com/c72dfa/p/14527228.html