EF_EPOLL_CTL_FAST

Name

ul_epoll_ctl_fast

Default

1

Minimum

0

Maximum

1

Scope

per-process

Avoid system calls in epoll_ctl() when using an accelerated epoll implementation. System calls are deferred until epoll_wait() blocks, and in some cases removed completely. This option improves performance for applications that call epoll_ctl() frequently.

Caveats:

• This option has no effect when EF_UL_EPOLL=0.
• Do not turn this option on if your application uses dup(), fork() or exec() with epoll file descriptors or with the sockets monitored by epoll.
• If you monitor the epoll fd in another poll, select or epoll set, and have this option enabled, it might not give correct results.
• If you monitor the epoll fd in another poll, select or epoll set, and the effects of epoll_ctl() are latency critical, then this option can cause latency spikes or even deadlock.
• With EF_UL_EPOLL=2, this option is harmful if you are calling epoll_wait() and epoll_ctl() simultaneously from different threads or processes.