xref: /freebsd/usr.bin/renice/renice.8 (revision 09e8dea79366f1e5b3a73e8a271b26e4b6bf2e6a)
1.\" Copyright (c) 1983, 1991, 1993
2.\"	The Regents of the University of California.  All rights reserved.
3.\"
4.\" Redistribution and use in source and binary forms, with or without
5.\" modification, are permitted provided that the following conditions
6.\" are met:
7.\" 1. Redistributions of source code must retain the above copyright
8.\"    notice, this list of conditions and the following disclaimer.
9.\" 2. Redistributions in binary form must reproduce the above copyright
10.\"    notice, this list of conditions and the following disclaimer in the
11.\"    documentation and/or other materials provided with the distribution.
12.\" 3. All advertising materials mentioning features or use of this software
13.\"    must display the following acknowledgement:
14.\"	This product includes software developed by the University of
15.\"	California, Berkeley and its contributors.
16.\" 4. Neither the name of the University nor the names of its contributors
17.\"    may be used to endorse or promote products derived from this software
18.\"    without specific prior written permission.
19.\"
20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30.\" SUCH DAMAGE.
31.\"
32.\"     @(#)renice.8	8.1 (Berkeley) 6/9/93
33.\" $FreeBSD$
34.\"
35.Dd June 9, 1993
36.Dt RENICE 8
37.Os
38.Sh NAME
39.Nm renice
40.Nd alter priority of running processes
41.Sh SYNOPSIS
42.Nm
43.Op Ar priority | Op Fl n Ar increment
44.Op Oo Fl p Oc Ar pid ...
45.Op Oo Fl g Oc Ar pgrp ...
46.Op Oo Fl u Oc Ar user ...
47.Sh DESCRIPTION
48.Nm Renice
49alters the
50scheduling priority of one or more running processes.
51The following
52.Ar who
53parameters are interpreted as process ID's, process group
54ID's, user ID's or user names.
55.Nm Renice Ns 'ing
56a process group causes all processes in the process group
57to have their scheduling priority altered.
58.Nm Renice Ns 'ing
59a user causes all processes owned by the user to have
60their scheduling priority altered.
61By default, the processes to be affected are specified by
62their process ID's.
63.Pp
64Options supported by
65.Nm :
66.Bl -tag -width Ds
67.It Fl g
68Force
69.Ar who
70parameters to be interpreted as process group ID's.
71.It Fl n
72Instead of changing the specified processes to the given priority,
73interpret the following argument as an increment to be applied to
74the current priority of each process.
75.It Fl u
76Force the
77.Ar who
78parameters to be interpreted as user names or user ID's.
79.It Fl p
80Resets the
81.Ar who
82interpretation to be (the default) process ID's.
83.El
84.Pp
85For example,
86.Pp
87.Dl "renice +1 987 -u daemon root -p 32"
88.Pp
89would change the priority of process ID's 987 and 32, and
90all processes owned by users daemon and root.
91.Pp
92Users other than the super-user may only alter the priority of
93processes they own,
94and can only monotonically increase their ``nice value''
95within the range 0 to
96.Dv PRIO_MAX
97(20).
98(This prevents overriding administrative fiats.)
99The super-user
100may alter the priority of any process
101and set the priority to any value in the range
102.Dv PRIO_MIN
103(\-20)
104to
105.Dv PRIO_MAX .
106Useful priorities are:
10720 (the affected processes will run only when nothing else
108in the system wants to),
1090 (the ``base'' scheduling priority),
110anything negative (to make things go very fast).
111.Sh FILES
112.Bl -tag -width /etc/passwd -compact
113.It Pa /etc/passwd
114to map user names to user ID's
115.El
116.Sh SEE ALSO
117.Xr nice 1 ,
118.Xr rtprio 1 ,
119.Xr getpriority 2 ,
120.Xr setpriority 2
121.Sh STANDARDS
122The
123.Nm
124utility conforms to
125.St -p1003.1-2001 .
126.Sh HISTORY
127The
128.Nm
129command appeared in
130.Bx 4.0 .
131.Sh BUGS
132Non super-users cannot increase scheduling priorities of their own processes,
133even if they were the ones that decreased the priorities in the first place.
134