1.\" Copyright (c) 2005 Nate Lawson 2.\" 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.\" 13.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 14.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 16.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 17.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 18.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 19.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 20.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 21.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 22.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 23.\" SUCH DAMAGE. 24.\" 25.\" $FreeBSD$ 26.\" 27.Dd December 24, 2008 28.Dt POWERD 8 29.Os 30.Sh NAME 31.Nm powerd 32.Nd "system power control utility" 33.Sh SYNOPSIS 34.Nm 35.Op Fl a Ar mode 36.Op Fl b Ar mode 37.Op Fl i Ar percent 38.Op Fl n Ar mode 39.Op Fl p Ar ival 40.Op Fl P Ar pidfile 41.Op Fl r Ar percent 42.Op Fl v 43.Sh DESCRIPTION 44The 45.Nm 46utility monitors the system state and sets various power control options 47accordingly. 48It offers three modes (maximum, minimum, and adaptive) that can be 49individually selected while on AC power or batteries. 50The modes maximum, minimum, adaptive and hiadaptive may be abbreviated 51max, min, adp, hadp. 52.Pp 53Maximum mode chooses the highest performance values. 54Minimum mode selects the lowest performance values to get the most power 55savings. 56Adaptive mode attempts to strike a balance by degrading performance when 57the system appears idle and increasing it when the system is busy. 58It offers a good balance between a small performance loss for greatly 59increased power savings. 60Hiadaptive mode is alike adaptive mode, but tuned for systems where 61performance and interactivity are more important then power consumption. 62It rises frequency faster, drops slower and keeps twice lower CPU load. 63The default mode is adaptive for battery power and hiadaptive for the rest. 64.Pp 65The 66.Nm 67utility recognizes the following runtime options: 68.Bl -tag -width ".Fl r Ar percent" 69.It Fl a Ar mode 70Selects the 71.Ar mode 72to use while on AC power. 73.It Fl b Ar mode 74Selects the 75.Ar mode 76to use while on battery power. 77.It Fl i Ar percent 78Specifies the CPU load percent level when adaptive 79mode should begin to degrade performance to save power. 80The default is 50% or lower. 81.It Fl n Ar mode 82Selects the 83.Ar mode 84to use normally when the AC line state is unknown. 85.It Fl p Ar ival 86Specifies a different polling interval (in milliseconds) for AC line state 87and system idle levels. 88The default is 250 ms. 89.It Fl P Ar pidfile 90Specifies an alternative file in which the process ID should be stored. 91The default is 92.Pa /var/run/powerd.pid . 93.It Fl r Ar percent 94Specifies the CPU load percent level where adaptive 95mode should consider the CPU running and increase performance. 96The default is 75% or higher. 97.It Fl v 98Verbose mode. 99Messages about power changes will be printed to stdout and 100.Nm 101will operate in the foreground. 102.El 103.Sh SEE ALSO 104.Xr acpi 4 , 105.Xr apm 4 , 106.Xr cpufreq 4 107.Sh HISTORY 108The 109.Nm 110utility first appeared in 111.Fx 6.0 . 112.Sh AUTHORS 113.An -nosplit 114.An Colin Percival 115first wrote 116.Nm estctrl , 117the utility that 118.Nm 119is based on. 120.An Nate Lawson 121then updated it for 122.Xr cpufreq 4 , 123added features, and wrote this manual page. 124.Sh BUGS 125The 126.Nm 127utility should also power down idle disks and other components besides the CPU. 128.Pp 129If 130.Nm 131is used with 132.Pa power_profile , 133they may override each other. 134.Pp 135The 136.Nm 137utility 138should probably use the 139.Xr devctl 4 140interface instead of polling for AC line state. 141