NAME
renice - alter priority of running processes

SYNOPSIS
renice priority [ [ -p ] pid ... ] [ [ -g ] pgrp ... ] [ [ -u ]
user ... ]

DESCRIPTION
Renice alters the scheduling priority of one or more running
processes. The who parameters are interpreted as process ID’s,
process group ID’s, 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. By default,
the processes to be affected are specified by their process ID’s.
To force who parameters to be interpreted as process group ID’s, a
-g may be specified. To force the who parameters to be interpreted
as user names, a -u may be given. Supplying -p will reset who
interpretation to be (the default) process ID’s. For example,

renice +1 987 -u daemon root -p 32

would change the priority of process ID’s 987 and 32, and all
processes owned by users daemon and root.

Users other than the super-user may only alter the priority of
processes they own, and can only monotonically increase their
"nice value" within the range 0 to PRIO_MAX (20). (This prevents
overriding administrative fiats.) The super-user may alter the
priority of any process and set the priority to any value in the
range PRIO_MIN (-20) to PRIO_MAX. Useful priorities are: 20 (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).

FILES
/etc/passwd to map user names to user ID’s

SEE ALSO
getpriority(2), setpriority(2)

BUGS
Non super-users can not increase scheduling priorities of their own
processes, even if they were the ones that decreased the priorities
in the first place.