Hi!

I’m trying to run some encoding jobs in the background, with a raised niceness so they won’t interfere with my normal work. I’m using ab-av1 and when I tried to just run nice -n 19 ab-av1 […], both ps and btop showed that the child ffmpeg command was still running at a niceness of 9, so I investigated why this may be. First I though this is just because nice doesn’t propagate to child commands regularly, so I reran the thing as nice -n 19 zsh -c ‘ab-av1 […]’, hoping that ecapsulation it all in a seperate shell might help. This did not work. Both btop and ps show the zsh instance running at -4, ab-av1 running at 15, and the ffmpeg child command still running at 9. Using renice to change the niceness after starting the processes did seem to work reliably though, but did not actually force newly created child processes to also use the set niceness (i. e., when ab-av1 spawns a new ffmpeg instance, that is set to a niceness of 9 again, even when ab-av1 is set to 19).

I’ve read the man page for nice and did some more searching, but I couldn’t find anything on why setting a niceness may not be working. Why doesn’t nice seem to work? Is this a product of CachyOS performance improvements and scheduling? Or am I just doing something wrong?

All the best, and thanks in advance for any help.

Thanks for the advice! Do you where I can find some proper documentation for ananicy-cpp? I couldn’t find any on the project page, and the Arch wiki is pretty sparse about it too…