1.\" $NetBSD: renice.8,v 1.13 2009/04/08 13:20:23 joerg Exp $ 2.\" 3.\" Copyright (c) 1983, 1991, 1993 4.\" The Regents of the University of California. All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 3. Neither the name of the University nor the names of its contributors 15.\" may be used to endorse or promote products derived from this software 16.\" without specific prior written permission. 17.\" 18.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 19.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 22.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28.\" SUCH DAMAGE. 29.\" 30.\" from: @(#)renice.8 8.1 (Berkeley) 6/9/93 31.\" $NetBSD: renice.8,v 1.13 2009/04/08 13:20:23 joerg Exp $ 32.\" 33.Dd June 9, 1993 34.Dt RENICE 8 35.Os 36.Sh NAME 37.Nm renice 38.Nd alter priority of running processes 39.Sh SYNOPSIS 40.Nm 41.Ar priority 42.Oo 43.Op Fl p 44.Ar pid ... 45.Oc 46.Oo 47.Fl g 48.Ar pgrp ... 49.Oc 50.Oo 51.Fl u 52.Ar user ... 53.Oc 54.Nm 55.Fl n 56.Ar increment 57.Oo 58.Op Fl p 59.Ar pid ... 60.Oc 61.Oo 62.Fl g 63.Ar pgrp ... 64.Oc 65.Oo 66.Fl u 67.Ar user ... 68.Oc 69.Sh DESCRIPTION 70.Nm 71alters the 72scheduling priority of one or more running processes. 73The following 74.Ar who 75parameters are interpreted as process ID's, process group 76ID's, or user names. 77.Nm Ns 'ing 78a process group causes all processes in the process group 79to have their scheduling priority altered. 80.Nm Ns 'ing 81a user causes all processes owned by the user to have 82their scheduling priority altered. 83By default, the processes to be affected are specified by 84their process ID's. 85.Pp 86Options supported by 87.Nm : 88.Bl -tag -width Ds 89.It Fl g 90Force 91.Ar who 92parameters to be interpreted as process group ID's. 93.It Fl n 94Instead of changing the specified processes to the given priority, 95interpret the following argument as an increment to be applied to 96the current priority of each process. 97.It Fl u 98Force the 99.Ar who 100parameters to be interpreted as user names. 101.It Fl p 102Resets the 103.Ar who 104interpretation to be (the default) process ID's. 105.El 106.Pp 107For example, 108.Bd -literal -offset indent 109renice +1 987 -u daemon root -p 32 110.Ed 111.Pp 112would change the priority of process ID's 987 and 32, and 113all processes owned by users daemon and root. 114.Pp 115Users other than the super-user may only alter the priority of 116processes they own, 117and can only monotonically increase their ``nice value'' 118within the range 0 to 119.Dv PRIO_MAX 120(20). 121(This prevents overriding administrative fiats.) 122The super-user 123may alter the priority of any process 124and set the priority to any value in the range 125.Dv PRIO_MIN 126(\-20) 127to 128.Dv PRIO_MAX . 129.Pp 130Useful priorities are: 1310, the ``base'' scheduling priority; 13220, the affected processes will run only when nothing at the base priority 133wants to; 134anything negative, the processes will receive a scheduling preference. 135.Sh FILES 136.Bl -tag -width /etc/passwd -compact 137.It Pa /etc/passwd 138to map user names to user ID's 139.El 140.Sh SEE ALSO 141.Xr nice 1 , 142.Xr getpriority 2 , 143.Xr setpriority 2 144.Sh HISTORY 145The 146.Nm 147command appeared in 148.Bx 4.0 . 149.Sh BUGS 150Non super-users can not increase scheduling priorities of their own processes, 151even if they were the ones that decreased the priorities in the first place. 152