作为c++开发，介绍i/o复用技术，epoll优于select的原因
I/O复用技术是指在一个进程中，同时处理多个I/O请求的一种技术。传统的I/O处理方式是多线程或多进程，这种方式的缺点是需要为每一个I/O请求创建一个线程或进程，这将消耗大量的系统资源。I/O复用技术则可以避免这个问题，它可以在一个线程中同时处理多个I/O请求，从而提高系统的效率。 Epoll是Linux内核2.6版本之后引入的一种I/O复用技术，它基于事件驱动的I/O模型，可以处理大量的I/O请求，而且效率非常高。Epoll与传统的I/O复用技术（如select、poll）相比，有以下几个优点： 1. epoll可以处理大量的I/O请求。传统的I/O复用技术在处理大量的I/O请求时，性能会下降，而Epoll则不会。 2. epoll的效率非常高。Epoll是通过内核来实现的，所以它的效率非常高。相比之下，传统的I/O复用技术需要通过系统调用来实现，所以效率较低。 3. epoll可以处理各种类型的I/O事件。Epoll可以处理读事件、写事件和异常事件，而传统的I/O复用技术只能处理读事件和写事件。 4. epoll可以实现非阻塞I/O。Epoll可以通过设置标志来实现非阻塞I/O，而传统的I/O复用技术则不能。 Epoll是I/O复用技术的一种非常优秀的实现，它可以大大提高系统的效率和性能。 [2023-11-09 00:49:21 | AI写代码神器 | 312点数解答]
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