Yes, I should have specified - in theory io_uring is much faster and less resource intensive. With the right polish, it can certainly be the next iteration of I/O syscalls.
That being said, you have to restructure a lot of your application in order to be io_uring ready in order to reap the most gains. In theory, you'll also have to be a bit pickier with CPU affinities, namely when using SQPOLL (submit queue poll), which creates a kernel thread. Too much contention means such facilities will actually slow you down.
The research is changing weekly and most of the exciting stuff is still on development branches, so tl;dr (for the rest of the readers) if you're on the fence, best stick to epoll for now.
That being said, you have to restructure a lot of your application in order to be io_uring ready in order to reap the most gains. In theory, you'll also have to be a bit pickier with CPU affinities, namely when using SQPOLL (submit queue poll), which creates a kernel thread. Too much contention means such facilities will actually slow you down.
The research is changing weekly and most of the exciting stuff is still on development branches, so tl;dr (for the rest of the readers) if you're on the fence, best stick to epoll for now.