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Using io_uring to make a high-performance finger server

by smlckz on 5/24/21, 11:31 AM with 16 comments

by Zababa on 5/24/21, 8:10 PM
I tried to use finger in Ubuntu, and it doesn't display UTF-8 correctly. It seems that a patch would fix this but it's been untouched for 6 years https://bugs.launchpad.net/ubuntu/+source/bsd-finger/+bug/46...
by rwmj on 5/24/21, 6:20 PM
I'm missing some "high level" context about io_uring, I might as well ask here:
- If I want to write a multithreaded program, is it best to have one io_uring per thread?
- Per CPU core?
- Per device or PCIe lane to the device? (It might make sense ...)
- Or one for the whole program? (Will Linux distribute requests across cores and run them in parallel for me?)
- If I'm writing a library that uses io_uring, should I create my own io_uring or offer an interface to add requests to one which the main program creates? (Or perhaps both?)

by Zababa on 5/24/21, 12:11 PM

  const grent = match (passwd::getgroup(group)) {
    void => fmt::fatal("No '{}' group available", group),
    gr: passwd::grent => gr,
  };

Interesting, is void being used as the "None" of an option type here? At least that's what it looks like to me.