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powerd(8) [freebsd man page]

POWERD(8)						    BSD System Manager's Manual 						 POWERD(8)

powerd -- system power control utility SYNOPSIS
powerd [-a mode] [-b mode] [-i percent] [-m freq] [-M freq] [-n mode] [-p ival] [-P pidfile] [-r percent] [-v] DESCRIPTION
The powerd utility monitors the system state and sets various power control options accordingly. It offers power-saving modes that can be individually selected for operation on AC power or batteries. maximum Choose the highest performance values. May be abbreviated as max. minimum Choose the lowest performance values to get the most power savings. May be abbreviated as min. adaptive Attempt to strike a balance by degrading performance when the system appears idle and increasing it when the system is busy. It offers a good balance between a small performance loss for greatly increased power savings. May be abbreviated as adp. hiadaptive Like adaptive mode, but tuned for systems where performance and interactivity are more important than power consumption. It increases frequency faster, reduces frequency less aggressively, and will maintain full frequency for longer. May be abbreviated as hadp. The default mode is adaptive for battery power and hiadaptive for the rest. powerd recognizes these runtime options: -a mode Selects the mode to use while on AC power. -b mode Selects the mode to use while on battery power. -i percent Specifies the CPU load percent level when adaptive mode should begin to degrade performance to save power. The default is 50% or lower. -m freq Specifies the minimum frequency to throttle down to. -M freq Specifies the maximum frequency to throttle up to. -n mode Selects the mode to use normally when the AC line state is unknown. -p ival Specifies a different polling interval (in milliseconds) for AC line state and system idle levels. The default is 250 ms. -P pidfile Specifies an alternative file in which the process ID should be stored. The default is /var/run/ -r percent Specifies the CPU load percent level where adaptive mode should consider the CPU running and increase performance. The default is 75% or higher. -v Verbose mode. Messages about power changes will be printed to stdout and powerd will operate in the foreground. SEE ALSO
acpi(4), apm(4), cpufreq(4) HISTORY
The powerd utility first appeared in FreeBSD 6.0. AUTHORS
Colin Percival first wrote estctrl, the utility that powerd is based on. Nate Lawson then updated it for cpufreq(4), added features, and wrote this manual page. BUGS
The powerd utility should also power down idle disks and other components besides the CPU. If powerd is used with power_profile, they may override each other. The powerd utility should probably use the devctl(4) interface instead of polling for AC line state. BSD
July 4, 2013 BSD

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POWERD(8)						      System Manager's Manual							 POWERD(8)

powerd - UPS monitoring daemon SYNOPSIS
/sbin/powerd [tty] DESCRIPTION
powerd monitors the serial port connected to an UPS device and will perform an unattended shutdown of the system if the UPS is on battery longer than a specified number of minutes. powerd needs to watch a tty with modem control properties. Please refer to the powerd documen- tation for further information. powerd also has the capabilities of notifying other clients on the network that may have a UPS but not be connected to the serial line that there is a power outage, and id configured through the powerd.conf file CONFIGURATION FILE
Here is the configuration format: Lines beginning with '#' are ignored. MODE <mode> specifies the mode the UPS should be in. Valid arguements are MONITOR and PEER MONITOR being the mode to actually watch a UPS serial port, and PEER being to listen for a connection from a machine in MONITOR mode MONITOR <device> Specifies which device to monitor while in MONITOR mode. Specify an actual device file. Example: /dev/ttyS0 POWERFAIL <line> <high|low> Specifies which lines on the serial ports indicate that the power is out. Valid arguements are DCD, CAR, CTS, and RNG. Also specify if the line being HIGH or LOW indicates a power failure. Since most people may not know this arguement, Please use the enclosed upsdetect program to automatically find this line. NOTIFY <hostname[:port]> <password> Specified in MONITOR mode to notify a client running in PEER mode. Specify the hostname of the machine, and optional port the daemon is running on, And the password as specified by their LISTEN command. See below for more details. LISTEN <hostname> <password> Specified in PEER mode, specifies a hostname that is allowed to notify us of when the power is out, and the password they shall give us to authenticate themselves. The 2 passwords should match on the MONITOR mode machines NOTIFY password, and the PEER modes LISTEN password. LISTENPORT <port> Specified in PEER mode, specifies the port that powerd should listen on. If you use this arguement, powerd shall not default to using port 532, and the machine in MONITOR mode must specify the port you use in their NOTIFY command. DELAY <delayinseconds> Specifies how many seconds before notifying init of a power outage. Note that this doesnt mean that the system will shut down in that many seconds, as it depends on how init is configured. Init usually issues a 2 min shutdown. USER <username> Specifies which username to drop to from root. The program will reobtain root access only when it needs to, Like when notifying init that the power is out. This is simply a security feature, and not needed for powerd to operate. Note: powerd must still be run ini- tially as root. It will then drop to the user if, and only if, a username is specified. ARGUMENTS
None: Please use the configuration file /etc/powerd.conf which can be generated with detectups. See detectups(8) for more information FILES
/etc/powerd.conf powerd configuration file /etc/powerstatus indicates line power status /etc/inittab init is what actually issues the shutdown SEE ALSO
powerd(8), shutdown(8), wall(1), init(8), inittab(5). AUTHOR
James Brents <> (with parts of this man page borrowed from all over the Linux community) POWERD(8)
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