*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.
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*(1p) 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).
== HISTORY
The *renice* command appeared in 4.0BSD.
== EXAMPLES
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: