[cturner]

Separate to the complexity highlighted here, there are a number of operations where there is no readiness mechanism available. For example - file open, file stat. These syscalls can cause significant thread blocks. For example, when operating against NFS.

DNS resolution is also fiddly to do in a robust, nonblocking, async manner. An in-kernel dns resolution can block its thread for several minutes.

With io_uring, there will be no need to use multithreading or process pools to mitigate these situations. io_uring enables a pure-async programming style that has never before been practical on a mainstream os.