epoll
A Linux readiness-notification interface designed to monitor large numbers of file descriptors without repeatedly scanning every descriptor.
Linux Context
epoll provides readiness notification for large sets of file descriptors without requiring an application to scan every descriptor repeatedly. Event-driven network servers can therefore manage many sockets with a limited number of event-loop threads.
I/O Boundary
epoll reports readiness; it is not itself asynchronous completion I/O. Edge-triggered and level-triggered modes also impose different requirements for draining data and rechecking readiness.
Related Linux Concepts
- io_uring
- System Call
- Event Loop
- Non-Blocking I/O