LouZai

Jan 29, 2024 · Interview Experience

Why Is epoll So Fast? Deep Dive into Its Data Structures, Locking and ET/LT Modes

This article systematically explains epoll’s internal data structures, how the protocol stack notifies it, the locking strategy for thread safety, the differences between edge‑triggered and level‑triggered modes, and why it outperforms select/poll in high‑concurrency Linux I/O.