xref: /freebsd/usr.bin/renice/renice.8 (revision 445ed7b40948c160f2f7d363d2d0ae1ffac4aabd)
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28.\"     @(#)renice.8	8.1 (Berkeley) 6/9/93
29.\" $FreeBSD$
30.\"
31.Dd June 9, 1993
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 p Oc Ar pid ...
41.Op Oo Fl g Oc Ar pgrp ...
42.Op Oo Fl u Oc Ar user ...
43.Nm
44.Fl n Ar increment
45.Op Oo Fl p Oc Ar pid ...
46.Op Oo Fl g Oc Ar pgrp ...
47.Op Oo Fl u Oc Ar user ...
48.Sh DESCRIPTION
49The
50.Nm
51utility alters the
52scheduling priority of one or more running processes.
53The following
54.Ar who
55parameters are interpreted as process ID's, process group
56ID's, user ID's or user names.
57The
58.Nm Ns 'ing
59of a process group causes all processes in the process group
60to have their scheduling priority altered.
61The
62.Nm Ns 'ing
63of a user causes all processes owned by the user to have
64their scheduling priority altered.
65By default, the processes to be affected are specified by
66their process ID's.
67.Pp
68The following options are available:
69.Bl -tag -width indent
70.It Fl g
71Force
72.Ar who
73parameters to be interpreted as process group ID's.
74.It Fl n
75Instead of changing the specified processes to the given priority,
76interpret the following argument as an increment to be applied to
77the current priority of each process.
78.It Fl u
79Force the
80.Ar who
81parameters to be interpreted as user names or user ID's.
82.It Fl p
83Reset the
84.Ar who
85interpretation to be (the default) process ID's.
86.El
87.Pp
88Users other than the super-user may only alter the priority of
89processes they own,
90and can only monotonically increase their ``nice value''
91within the range 0 to
92.Dv PRIO_MAX
93(20).
94(This prevents overriding administrative fiats.)
95The super-user
96may alter the priority of any process
97and set the priority to any value in the range
98.Dv PRIO_MIN
99(\-20)
100to
101.Dv PRIO_MAX .
102Useful priorities are:
10320 (the affected processes will run only when nothing else
104in the system wants to),
1050 (the ``base'' scheduling priority),
106anything negative (to make things go very fast).
107.Sh FILES
108.Bl -tag -width /etc/passwd -compact
109.It Pa /etc/passwd
110to map user names to user ID's
111.El
112.Sh EXAMPLES
113Change the priority of process ID's 987 and 32, and
114all processes owned by users daemon and root.
115.Pp
116.Dl "renice +1 987 -u daemon root -p 32"
117.Sh SEE ALSO
118.Xr nice 1 ,
119.Xr rtprio 1 ,
120.Xr getpriority 2 ,
121.Xr setpriority 2
122.Sh STANDARDS
123The
124.Nm
125utility conforms to
126.St -p1003.1-2001 .
127.Sh HISTORY
128The
129.Nm
130utility appeared in
131.Bx 4.0 .
132.Sh BUGS
133Non super-users cannot increase scheduling priorities of their own processes,
134even if they were the ones that decreased the priorities in the first place.
135