xref: /freebsd/usr.bin/renice/renice.8 (revision ee2ea5ceafed78a5bd9810beb9e3ca927180c226)
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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.Oo
44.Ar priority |
45.Op Fl n Ar increment
46.Oc
47.Oo
48.Op Fl p
49.Ar pid ...
50.Oc
51.Oo
52.Op Fl g
53.Ar pgrp ...
54.Oc
55.Oo
56.Op Fl u
57.Ar user ...
58.Oc
59.Sh DESCRIPTION
60.Nm Renice
61alters the
62scheduling priority of one or more running processes.
63The following
64.Ar who
65parameters are interpreted as process ID's, process group
66ID's, or user names.
67.Nm Renice Ns 'ing
68a process group causes all processes in the process group
69to have their scheduling priority altered.
70.Nm Renice Ns 'ing
71a user causes all processes owned by the user to have
72their scheduling priority altered.
73By default, the processes to be affected are specified by
74their process ID's.
75.Pp
76Options supported by
77.Nm :
78.Bl -tag -width Ds
79.It Fl g
80Force
81.Ar who
82parameters to be interpreted as process group ID's.
83.It Fl n
84Instead of changing the specified processes to the given priority,
85interpret the following argument as an increment to be applied to
86the current priority of each process.
87.It Fl u
88Force the
89.Ar who
90parameters to be interpreted as user names.
91.It Fl p
92Resets the
93.Ar who
94interpretation to be (the default) process ID's.
95.El
96.Pp
97For example,
98.Bd -literal -offset
99renice +1 987 -u daemon root -p 32
100.Ed
101.Pp
102would change the priority of process ID's 987 and 32, and
103all processes owned by users daemon and root.
104.Pp
105Users other than the super-user may only alter the priority of
106processes they own,
107and can only monotonically increase their ``nice value''
108within the range 0 to
109.Dv PRIO_MAX
110(20).
111(This prevents overriding administrative fiats.)
112The super-user
113may alter the priority of any process
114and set the priority to any value in the range
115.Dv PRIO_MIN
116(\-20)
117to
118.Dv PRIO_MAX .
119Useful priorities are:
12020 (the affected processes will run only when nothing else
121in the system wants to),
1220 (the ``base'' scheduling priority),
123anything negative (to make things go very fast).
124.Sh FILES
125.Bl -tag -width /etc/passwd -compact
126.It Pa /etc/passwd
127to map user names to user ID's
128.El
129.Sh SEE ALSO
130.Xr nice 1 ,
131.Xr rtprio 1 ,
132.Xr getpriority 2 ,
133.Xr setpriority 2
134.Sh BUGS
135Non super-users cannot increase scheduling priorities of their own processes,
136even if they were the ones that decreased the priorities in the first place.
137.Sh HISTORY
138The
139.Nm
140command appeared in
141.Bx 4.0 .
142