DOKK / manpages / debian 10 / bsdutils / renice.1.en
RENICE(1) User Commands RENICE(1)

renice - alter priority of running processes

renice [-n] priority [-g|-p|-u] identifier...

renice alters the scheduling priority of one or more running processes. The first argument is the priority value to be used. The other arguments are interpreted as process IDs (by default), process group IDs, user IDs, or user names. renice'ing a process group causes all processes in the process group to have their scheduling priority altered. renice'ing a user causes all processes owned by the user to have their scheduling priority altered.

Specify the scheduling priority to be used for the process, process group, or user. Use of the option -n or --priority is optional, but when used it must be the first argument.
Interpret the succeeding arguments as process group IDs.
Interpret the succeeding arguments as process IDs (the default).
Interpret the succeeding arguments as usernames or UIDs.
Display version information and exit.
Display help text and exit.

The following command would change the priority of the processes with PIDs 987 and 32, plus all processes owned by the users daemon and root:

Users other than the superuser may only alter the priority of processes they own. Furthermore, an unprivileged user can only increase the ``nice value'' (i.e., choose a lower priority) and such changes are irreversible unless (since Linux 2.6.12) the user has a suitable ``nice'' resource limit (see ulimit(1) and getrlimit(2)).

The superuser may alter the priority of any process and set the priority to any value in the range -20 to 19. Useful priorities are: 19 (the affected processes will run only when nothing else in the system wants to), 0 (the ``base'' scheduling priority), anything negative (to make things go very fast).

/etc/passwd
to map user names to user IDs

nice(1), getpriority(2), setpriority(2), credentials(7), sched(7)

The renice command appeared in 4.0BSD.

The renice command is part of the util-linux package and is available from Linux Kernel Archive.

July 2014 util-linux