sys-utils/renice.1

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.\"     @(#)renice.8   8.1 (Berkeley) 6/9/93
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.TH RENICE "1" "July 2014" "util-linux" "User Commands"
.SH NAME
renice \- alter priority of running processes
.SH SYNOPSIS
.B renice
.RB [ \-n ]
.I priority
.RB [ \-g | \-p | \-u ]
.IR identifier ...
.SH DESCRIPTION
.B renice
alters the scheduling priority of one or more running processes.  The
first argument is the \fIpriority\fR value to be used.
The other arguments are interpreted as process IDs (by default),
process group IDs, user IDs, or user names.
.BR renice 'ing
a process group causes all processes in the process group to have their
scheduling priority altered.
.BR renice 'ing
a user causes all processes owned by the user to have their scheduling
priority altered.
.PP
.SH OPTIONS
.TP
.BR \-n , " \-\-priority " \fIpriority\fR
Specify the scheduling
.I priority
to be used for the process, process group, or user.  Use of the option
.BR \-n " or " \-\-priority
is optional, but when used it must be the first argument.
.TP
.BR \-g , " \-\-pgrp
Interpret the succeeding arguments as process group IDs.
.TP
.BR \-p , " \-\-pid
Interpret the succeeding arguments as process IDs
(the default).
.TP
.BR \-u , " \-\-user
Interpret the succeeding arguments as usernames or UIDs.
.TP
.BR \-h , " \-\-help"
Display help text and exit.
.TP
.BR \-V , " \-\-version"
Display version information and exit.
.SH 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:
.TP
.B "       renice" +1 987 -u daemon root -p 32
.SH NOTES
Users other than the superuser may only alter the priority of processes they
own, and can only monotonically increase their ``nice value'' (for security
reasons) within the range 0 to 19,
unless a nice resource limit is set (Linux 2.6.12 and higher).  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).
.SH FILES
.TP
.B /etc/passwd
to map user names to user IDs
.SH SEE ALSO
.BR getpriority (2),
.BR setpriority (2)
.SH BUGS
Non-superusers cannot increase scheduling priorities of their own processes,
even if they were the ones that decreased the priorities in the first place.
.PP
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.
.SH HISTORY
The
.B renice
command appeared in 4.0BSD.
.SH AVAILABILITY
The renice command is part of the util-linux package and is available from
.UR ftp://\:ftp.kernel.org\:/pub\:/linux\:/utils\:/util-linux/
Linux Kernel Archive
.UE .