The author delves into the world of IRCDs, exploring the kqueue vs epoll debate within the community of IRCD administrators. They explain the historical development of polling APIs like select and poll, leading to the introduction of kqueue in BSD systems and epoll in Linux. The article highlights the differences between kqueue and epoll in terms of event filters and kernel handles, arguing that epoll’s composable design makes it a more flexible and less technically encumbered choice. The comparison of commonly used event filters and their equivalents in Linux showcases this advantage. Surprisingly, FreeBSD has recently added support for Linux’s eventfd, hinting at a potential convergence of the two systems.
https://ariadne.space/2021/06/06/actually-bsd-kqueue-is-a-mountain-of-technical-debt/