作为c++开发,select和epoll实现区别


`select`和`epoll`都是用于多路复用的系统调用,它们的主要区别在于以下几个方面: 1. 并发性:`select`的并发性较差,每次只能处理一个文件描述符,而`epoll`可以处理大量的文件描述符,因此在高并发的情况下,`epoll`的性能更好。 2. 内存消耗:`select`需要维护一个文件描述符列表,而`epoll`只需要维护一个事件列表,因此在处理大量的文件描述符时,`epoll`的内存消耗更小。 3. 管道效率:`epoll`使用事件驱动的方式,当文件描述符有事件发生时,会立即通知应用程序,而`select`需要定期轮询文件描述符列表,因此在处理大量的文件描述符时,`epoll`的效率更高。 4. 功能:`epoll`支持更多的功能,例如边缘触发和水平触发,而`select`只支持边缘触发。 5. 系统支持:`epoll`是Linux特有的,而`select`是跨平台的。 `epoll`在高并发、大量文件描述符的情况下,性能更好,而`select`则更适合于低并发、少量文件描述符的情况。 [2023-11-09 00:43:40 | AI写代码神器 | 272点数解答]
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