A while ago linux introduced io_uring (https://kernel.dk/io_ur | The lazy guy channel

A while ago linux introduced io_uring (https://kernel.dk/io_uring.pdf) interface for dealing with asynchronous I/O with minimal syscall overhead. Latest Linux kernels extend this API to support more and more non-I/O related syscalls in async manner. I advise to read about this API, it is at the same time ingeniously simple, smart, and efficient. And looks like this is a future of high-performance server applications.

It’s funny how Linux has essentially reinvented low-overhead asynchronous message-passing for doing syscalls. Something that microkernels had to invent ages ago to be somewhat competitive in performance with monolithic kernels.

Tangentially related. I guess, at least some of my readers are not aware of famous Tannenbaum-Torvalds debate. It is an entertaining read: https://groups.google.com/forum/#!topic/comp.os.minix/wlhw16QWltI%5B1-25%5D. Touching monolithic vs microkernel design.