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 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