modules/nix-daemon: Explain nice level limitations

This commit is contained in:
Mikael Voss 2021-09-24 14:48:01 +02:00
parent 1a6a4817e8
commit 5f9e069984
No known key found for this signature in database
GPG Key ID: D991B1833C467B03

View File

@ -181,6 +181,16 @@ in
description = ''
Nix daemon process priority. This priority propagates to build processes.
0 is the default Unix process priority, 19 is the lowest.
Please note that if used on a recent Linux kernel with group scheduling,
setting the nice level will only have an effect relative to other threads
in the same task group. Therefore this option is only useful if
autogrouping has been disabled (see the kernel.sched_autogroup_enabled
sysctl) and no systemd unit uses any of the per-service CPU accounting
features of systemd. Otherwise the Nix daemon process may be placed in a
separate task group and the nice level setting will have no effect.
Refer to the man pages sched(7) and systemd.resource-control(5) for
details.
'';
};