xref: /freebsd/usr.bin/renice/renice.8 (revision 6990ffd8a95caaba6858ad44ff1b3157d1efba8f)
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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.Ar priority
44.Oo
45.Op Fl p
46.Ar pid ...
47.Oc
48.Oo
49.Op Fl g
50.Ar pgrp ...
51.Oc
52.Oo
53.Op Fl u
54.Ar user ...
55.Oc
56.Sh DESCRIPTION
57.Nm Renice
58alters the
59scheduling priority of one or more running processes.
60The following
61.Ar who
62parameters are interpreted as process ID's, process group
63ID's, or user names.
64.Nm Renice Ns 'ing
65a process group causes all processes in the process group
66to have their scheduling priority altered.
67.Nm Renice Ns 'ing
68a user causes all processes owned by the user to have
69their scheduling priority altered.
70By default, the processes to be affected are specified by
71their process ID's.
72.Pp
73Options supported by
74.Nm :
75.Bl -tag -width Ds
76.It Fl g
77Force
78.Ar who
79parameters to be interpreted as process group ID's.
80.It Fl u
81Force the
82.Ar who
83parameters to be interpreted as user names.
84.It Fl p
85Resets the
86.Ar who
87interpretation to be (the default) process ID's.
88.El
89.Pp
90For example,
91.Bd -literal -offset
92renice +1 987 -u daemon root -p 32
93.Ed
94.Pp
95would change the priority of process ID's 987 and 32, and
96all processes owned by users daemon and root.
97.Pp
98Users other than the super-user may only alter the priority of
99processes they own,
100and can only monotonically increase their ``nice value''
101within the range 0 to
102.Dv PRIO_MAX
103(20).
104(This prevents overriding administrative fiats.)
105The super-user
106may alter the priority of any process
107and set the priority to any value in the range
108.Dv PRIO_MIN
109(\-20)
110to
111.Dv PRIO_MAX .
112Useful priorities are:
11320 (the affected processes will run only when nothing else
114in the system wants to),
1150 (the ``base'' scheduling priority),
116anything negative (to make things go very fast).
117.Sh FILES
118.Bl -tag -width /etc/passwd -compact
119.It Pa /etc/passwd
120to map user names to user ID's
121.El
122.Sh SEE ALSO
123.Xr nice 1 ,
124.Xr rtprio 1 ,
125.Xr getpriority 2 ,
126.Xr setpriority 2
127.Sh BUGS
128Non super-users cannot increase scheduling priorities of their own processes,
129even if they were the ones that decreased the priorities in the first place.
130.Sh HISTORY
131The
132.Nm
133command appeared in
134.Bx 4.0 .
135