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 November 6, 2005 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. 50.Pp 51Maximum mode chooses the highest performance values. 52Minimum mode selects the lowest performance values to get the most power 53savings. 54Adaptive mode attempts to strike a balance by degrading performance when 55the system appears idle and increasing it when the system is busy. 56It offers a good balance between a small performance loss for greatly 57increased power savings. 58The default mode is 59adaptive. 60.Pp 61The 62.Nm 63utility recognizes the following runtime options: 64.Bl -tag -width ".Fl r Ar percent" 65.It Fl a Ar mode 66Selects the 67.Ar mode 68to use while on AC power. 69.It Fl b Ar mode 70Selects the 71.Ar mode 72to use while on battery power. 73.It Fl i Ar percent 74Specifies the CPU idle percent level when 75adaptive 76mode should begin to degrade performance to save power. 77The default is 90% or higher. 78.It Fl n Ar mode 79Selects the 80.Ar mode 81to use normally when the AC line state is unknown. 82.It Fl p Ar ival 83Specifies a different polling interval (in milliseconds) for AC line state 84and system idle levels. 85The default is 500 ms. 86.It Fl P Ar pidfile 87Specifies an alternative file in which the process ID should be stored. 88The default is 89.Pa /var/run/powerd.pid . 90.It Fl r Ar percent 91Specifies the CPU idle percent level where 92adaptive 93mode should consider the CPU running and increase performance. 94The default is 65% or lower. 95.It Fl v 96Verbose mode. 97Messages about power changes will be printed to stdout and 98.Nm 99will operate in the foreground. 100.El 101.Sh SEE ALSO 102.Xr acpi 4 , 103.Xr apm 4 , 104.Xr cpufreq 4 105.Sh HISTORY 106The 107.Nm 108utility first appeared in 109.Fx 5.5 . 110.Sh AUTHORS 111.An -nosplit 112.An Colin Percival 113first wrote 114.Nm estctrl , 115the utility that 116.Nm 117is based on. 118.An Nate Lawson 119then updated it for 120.Xr cpufreq 4 , 121added features, and wrote this manual page. 122.Sh BUGS 123The 124.Nm 125utility should also power down idle disks and other components besides the CPU. 126.Pp 127If 128.Nm 129is used with 130.Pa power_profile , 131they may override each other. 132.Pp 133The 134.Nm 135utility 136should probably use the 137.Xr devctl 4 138interface instead of polling for AC line state. 139