NAME
renice - alter priority of running processes
SYNOPSIS
renice [-n] priority [[-p] pid ...] [[-g] pgrp ...] [[-u] user ...]
renice -h | -v
DESCRIPTION
Renice alters the scheduling priority of one or more running processes.
The following 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.
Options supported by renice:
-n, --priority
The scheduling priority of the process, process group, or user.
-g, --pgrp
Force who parameters to be interpreted as process group ID’s.
-u, --user
Force the who parameters to be interpreted as user names.
-p, --pid
Resets the who interpretation to be (the default) process ID’s.
-v, --version
Print version.
-h, --help
Print help.
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.
The Linux kernel (at least version 2.0.0) and linux libc (at least
version 5.2.18) does not agree entirely on what the specifics of the
systemcall interface to set nice values is. Thus causes renice to report
bogus previous nice values.
HISTORY
The renice command appeared in 4.0BSD.
AVAILABILITY
The renice command is part of the util-linux-ng package and is available
from ftp://ftp.kernel.org/pub/linux/utils/util-linux-ng/.