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 21, 2009 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 four modes (maximum, minimum, adaptive and hiadaptive) 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 like adaptive mode, but tuned for systems where 61performance and interactivity are more important then power consumption. 62It increases frequency faster, reduces the frequency less aggressively and 63will maintain full frequency for longer. 64The default mode is adaptive for battery power and hiadaptive for the rest. 65.Pp 66The 67.Nm 68utility recognizes the following runtime options: 69.Bl -tag -width ".Fl r Ar percent" 70.It Fl a Ar mode 71Selects the 72.Ar mode 73to use while on AC power. 74.It Fl b Ar mode 75Selects the 76.Ar mode 77to use while on battery power. 78.It Fl i Ar percent 79Specifies the CPU load percent level when adaptive 80mode should begin to degrade performance to save power. 81The default is 50% or lower. 82.It Fl n Ar mode 83Selects the 84.Ar mode 85to use normally when the AC line state is unknown. 86.It Fl p Ar ival 87Specifies a different polling interval (in milliseconds) for AC line state 88and system idle levels. 89The default is 250 ms. 90.It Fl P Ar pidfile 91Specifies an alternative file in which the process ID should be stored. 92The default is 93.Pa /var/run/powerd.pid . 94.It Fl r Ar percent 95Specifies the CPU load percent level where adaptive 96mode should consider the CPU running and increase performance. 97The default is 75% or higher. 98.It Fl v 99Verbose mode. 100Messages about power changes will be printed to stdout and 101.Nm 102will operate in the foreground. 103.El 104.Sh SEE ALSO 105.Xr acpi 4 , 106.Xr apm 4 , 107.Xr cpufreq 4 108.Sh HISTORY 109The 110.Nm 111utility first appeared in 112.Fx 6.0 . 113.Sh AUTHORS 114.An -nosplit 115.An Colin Percival 116first wrote 117.Nm estctrl , 118the utility that 119.Nm 120is based on. 121.An Nate Lawson 122then updated it for 123.Xr cpufreq 4 , 124added features, and wrote this manual page. 125.Sh BUGS 126The 127.Nm 128utility should also power down idle disks and other components besides the CPU. 129.Pp 130If 131.Nm 132is used with 133.Pa power_profile , 134they may override each other. 135.Pp 136The 137.Nm 138utility 139should probably use the 140.Xr devctl 4 141interface instead of polling for AC line state. 142