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 February 26, 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 mode 36.Op Fl b mode 37.Op Fl i percent 38.Op Fl n mode 39.Op Fl p ival 40.Op Fl r percent 41.Op Fl v 42.Sh DESCRIPTION 43The 44.Nm 45utility monitors the system state and sets various power control options 46accordingly. 47It offers three modes (max, min, and adaptive) that can be 48individually selected while on AC power or batteries. 49.Pp 50Maximum mode chooses the highest performance values. 51Minimum mode selects the lowest performance values to get the most power 52savings. 53Adaptive mode attempts to strike a balance by degrading performance when 54the system appears idle and increasing it when the system is busy. 55It offers a good balance between a small performance loss for greatly 56increased power savings. 57The default mode is 58adaptive. 59.Pp 60The 61.Nm 62utility recognizes the following runtime options: 63.Bl -tag -width -i_percent 64.It Fl a Ar mode 65Selects the 66.Ar mode 67to use while on AC power. 68.It Fl b Ar mode 69Selects the 70.Ar mode 71to use while on battery power. 72.It Fl i Ar percent 73Specifies the CPU idle percent level when 74adaptive 75mode should begin to degrade performance to save power. 76The default is 90% or higher. 77.It Fl n Ar mode 78Selects the 79.Ar mode 80to use normally when the AC line state is unknown. 81.It Fl p Ar ival 82Specifies a different polling interval (in milliseconds) for AC line state 83and system idle levels. 84The default is 500 ms. 85.It Fl r Ar percent 86Specifies the CPU idle percent level where 87adaptive 88mode should consider the CPU running and increase performance. 89The default is 80% or lower. 90.It Fl v 91Verbose mode. 92Messages about power changes will be printed to stdout and 93.Nm 94will operate in the foreground. 95.El 96.Sh SEE ALSO 97.Xr acpi 4 , 98.Xr apm 4 , 99.Xr cpufreq 4 100.Sh HISTORY 101The 102.Nm 103utility first appeared in 104.Fx 5.5 . 105.Sh AUTHORS 106.An Colin Percival 107first wrote 108.Pa estctrl , 109the utility that 110.Nm 111is based on. 112.An Nate Lawson 113then updated it for 114.Xr cpufreq 4 , 115added features, and wrote this man page. 116.Sh BUGS 117The 118.Nm 119utility should also power down idle disks and other components besides the CPU. 120.Pp 121If 122.Nm 123is used with power_profile, they may override each other. 124.Pp 125.Nm 126should probably use the 127.Xr devctl 4 128interface instead of polling for AC line state. 129