xref: /freebsd/usr.bin/renice/renice.8 (revision 8ddb146abcdf061be9f2c0db7e391697dafad85c)
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. Neither the name of the University nor the names of its contributors
13.\"    may be used to endorse or promote products derived from this software
14.\"    without specific prior written permission.
15.\"
16.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
17.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
20.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26.\" SUCH DAMAGE.
27.\"
28.\"     @(#)renice.8	8.1 (Berkeley) 6/9/93
29.\" $FreeBSD$
30.\"
31.Dd October 27, 2020
32.Dt RENICE 8
33.Os
34.Sh NAME
35.Nm renice
36.Nd alter priority of running processes
37.Sh SYNOPSIS
38.Nm
39.Ar priority
40.Op Oo Fl gpu Oc Ar target
41.Nm
42.Fl n Ar increment
43.Op Oo Fl gpu Oc Ar target
44.Sh DESCRIPTION
45The
46.Nm
47utility alters the
48scheduling priority of one or more running processes.
49The following
50.Ar target
51parameters are interpreted as process ID's (the default), process group
52ID's, user ID's or user names.
53The
54.Nm Ns 'ing
55of a process group causes all processes in the process group
56to have their scheduling priority altered.
57The
58.Nm Ns 'ing
59of a user causes all processes owned by the user to have
60their scheduling priority altered.
61.Pp
62The following options are available:
63.Bl -tag -width indent
64.It Fl n
65Instead of changing the specified processes to the given priority,
66interpret the following argument as an increment to be applied to
67the current priority of each process.
68.It Fl g
69Interpret
70.Ar target
71parameters as process group ID's.
72.It Fl p
73Interpret
74.Ar target
75parameters as process ID's (the default).
76.It Fl u
77Interpret
78.Ar target
79parameters as user names or user ID's.
80.El
81.Pp
82Users other than the super-user may only alter the priority of
83processes they own,
84and can only monotonically increase their ``nice value''
85within the range 0 to
86.Dv PRIO_MAX
87(20).
88(This prevents overriding administrative fiats.)
89The super-user
90may alter the priority of any process
91and set the priority to any value in the range
92.Dv PRIO_MIN
93(\-20)
94to
95.Dv PRIO_MAX .
96Useful priorities are:
9720 (the affected processes will run only when nothing else
98in the system wants to),
990 (the ``base'' scheduling priority),
100anything negative (to make things go very fast).
101.Sh FILES
102.Bl -tag -width /etc/passwd -compact
103.It Pa /etc/passwd
104to map user names to user ID's
105.El
106.Sh EXAMPLES
107Change the priority of process ID's 987 and 32, and
108all processes owned by users daemon and root.
109.Pp
110.Dl "renice +1 987 -u daemon root -p 32"
111.Sh SEE ALSO
112.Xr nice 1 ,
113.Xr rtprio 1 ,
114.Xr getpriority 2 ,
115.Xr setpriority 2
116.Sh STANDARDS
117The
118.Nm
119utility conforms to
120.St -p1003.1-2001 .
121.Sh HISTORY
122The
123.Nm
124utility appeared in
125.Bx 4.0 .
126.Sh BUGS
127Non super-users cannot increase scheduling priorities of their own processes,
128even if they were the ones that decreased the priorities in the first place.
129