A connection processing method can be selected explicitly with the use directive.
The following connection processing methods are supported:
select — standard method. The --with-select_module and --without-select_module configuration parameters can be used to forcibly enable or disable the build of this module.
poll — standard method. The --with-poll_module and --without-poll_module configuration parameters can be used to forcibly enable or disable the build of this module.
kqueue — efficient method used on FreeBSD 4.1+, OpenBSD 2.9+, NetBSD 2.0, and Mac OS X.
epoll — efficient method used on Linux 2.6+.
/dev/poll — efficient method used on Solaris 7 11/99+, HP/UX 11.22+ (eventport), IRIX 6.5.15+, and Tru64 UNIX 5.1A+.
eventport — event ports, efficient method used on Solaris 10.
Nginx(4) - Connection processing methods
原文：http://www.cnblogs.com/thlzhf/p/5175629.html