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. All advertising materials mentioning features or use of this software 13.\" must display the following acknowledgement: 14.\" This product includes software developed by the University of 15.\" California, Berkeley and its contributors. 16.\" 4. Neither the name of the University nor the names of its contributors 17.\" may be used to endorse or promote products derived from this software 18.\" without specific prior written permission. 19.\" 20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30.\" SUCH DAMAGE. 31.\" 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.Op Ar priority | Op Fl n Ar increment 44.Op Oo Fl p Oc Ar pid ... 45.Op Oo Fl g Oc Ar pgrp ... 46.Op Oo Fl u Oc Ar user ... 47.Sh DESCRIPTION 48The 49.Nm 50utility alters the 51scheduling priority of one or more running processes. 52The following 53.Ar who 54parameters are interpreted as process ID's, process group 55ID's, user ID's or user names. 56The 57.Nm Ns 'ing 58of a process group causes all processes in the process group 59to have their scheduling priority altered. 60The 61.Nm Ns 'ing 62of a user causes all processes owned by the user to have 63their scheduling priority altered. 64By default, the processes to be affected are specified by 65their process ID's. 66.Pp 67The following options are available: 68.Bl -tag -width indent 69.It Fl g 70Force 71.Ar who 72parameters to be interpreted as process group ID's. 73.It Fl n 74Instead of changing the specified processes to the given priority, 75interpret the following argument as an increment to be applied to 76the current priority of each process. 77.It Fl u 78Force the 79.Ar who 80parameters to be interpreted as user names or user ID's. 81.It Fl p 82Reset the 83.Ar who 84interpretation to be (the default) process ID's. 85.El 86.Pp 87For example, 88.Pp 89.Dl "renice +1 987 -u daemon root -p 32" 90.Pp 91would change the priority of process ID's 987 and 32, and 92all processes owned by users daemon and root. 93.Pp 94Users other than the super-user may only alter the priority of 95processes they own, 96and can only monotonically increase their ``nice value'' 97within the range 0 to 98.Dv PRIO_MAX 99(20). 100(This prevents overriding administrative fiats.) 101The super-user 102may alter the priority of any process 103and set the priority to any value in the range 104.Dv PRIO_MIN 105(\-20) 106to 107.Dv PRIO_MAX . 108Useful priorities are: 10920 (the affected processes will run only when nothing else 110in the system wants to), 1110 (the ``base'' scheduling priority), 112anything negative (to make things go very fast). 113.Sh FILES 114.Bl -tag -width /etc/passwd -compact 115.It Pa /etc/passwd 116to map user names to user ID's 117.El 118.Sh SEE ALSO 119.Xr nice 1 , 120.Xr rtprio 1 , 121.Xr getpriority 2 , 122.Xr setpriority 2 123.Sh STANDARDS 124The 125.Nm 126utility conforms to 127.St -p1003.1-2001 . 128.Sh HISTORY 129The 130.Nm 131utility appeared in 132.Bx 4.0 . 133.Sh BUGS 134Non super-users cannot increase scheduling priorities of their own processes, 135even if they were the ones that decreased the priorities in the first place. 136