renice(8)renice(8)Namerenice - alter priority of running processes
Syntax
/etc/renice priority [ [ -p ] pid ... ] [ [ -g ] pgrp ... ] [ [ -u ]
user ... ]
Description
The command alters the scheduling priority of one or more running pro‐
cesses. The who parameters are interpreted as process ID's, process
group ID's, or user names. Using on a process group causes all pro‐
cesses in the process group to have their scheduling priority altered.
Using on a user causes all processes owned by the user to have their
scheduling priority altered. By default, the processes to be affected
are specified by their process ID's.
Options
To force who parameters to be interpreted as process group ID's, a may
be specified. To force the who parameters to be interpreted as user
names, a may be given. Supplying will reset who interpretation to be
(the default) process ID's.
Users other than the superuser may only alter the priority of processes
they own, and can only monotonically increase their ``nice value''
within the range 0 to PRIO_MIN (20). (This prevents overriding admin‐
istrative fiats.) The superuser can alter the priority of any process
and set the priority to any value in the range PRIO_MAX (-20) to
PRIO_MIN. Useful priorities are: 19 (the affected processes will run
only when nothing else in the system wants to), 0 (the ``base'' sched‐
uling priority), anything negative (to make things go very fast).
Examples
The following command changes the priority of process ID's 987 and 32,
and all processes owned by users daemon and root:
/etc/renice +1 987 -u daemon root -p 32
Restrictions
If you make the priority very negative, then the process cannot be
interrupted. To regain control you make the priority greater than
zero. Non-superusers cannot increase scheduling priorities of their
own processes, even if they were the ones that decreased the priorities
in the first place.
Files
Maps user names to user IDs
See Alsogetpriority(2), setpriority(2)renice(8)