powerd(8) [freebsd man page]

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

NAME

     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/powerd.pid.

     -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

Check Out this Related Man Page

SYSMON_PSWITCH(9)					   BSD Kernel Developer's Manual					 SYSMON_PSWITCH(9)

NAME

     sysmon_pswitch -- framework for power switches

SYNOPSIS

     #include <dev/sysmon/sysmonvar.h>

     int
     sysmon_pswitch_register(struct sysmon_pswitch *smpsw);

     void
     sysmon_pswitch_unregister(struct sysmon_pswitch *smpsw);

     void
     sysmon_pswitch_event(struct sysmon_pswitch *smpsw, int event);

DESCRIPTION

     The machine-independent sysmon_pswitch provides a framework for power management.	The interface has been largely superceded by the pmf(9)
     framework, but sysmon_pswitch is still used to manage power switches as well as related mechanical adapters and buttons.  These are encapsu-
     lated in the following structure:

     struct sysmon_pswitch {
	     const char *smpsw_name;	     /* power switch name */
	     int smpsw_type;		     /* power switch type */

	     LIST_ENTRY(sysmon_pswitch) smpsw_list;
     };

     Unsurprisingly, smpsw_name specifies the name of the power switch and smpsw_type defines the type of it.  The following types are defined:

	   PSWITCH_TYPE_POWER
	   PSWITCH_TYPE_SLEEP
	   PSWITCH_TYPE_LID
	   PSWITCH_TYPE_RESET
	   PSWITCH_TYPE_ACADAPTER
	   PSWITCH_TYPE_HOTKEY

     If the type is PSWITCH_TYPE_HOTKEY, there are few predefined names that can be used for smpsw_name:

	   PSWITCH_HK_DISPLAY_CYCLE  display-cycle
	   PSWITCH_HK_LOCK_SCREEN    lock-screen
	   PSWITCH_HK_BATTERY_INFO   battery-info
	   PSWITCH_HK_EJECT_BUTTON   eject-button
	   PSWITCH_HK_ZOOM_BUTTON    zoom-button
	   PSWITCH_HK_VENDOR_BUTTON  vendor-button

     Once a power switch event has been proceeded, sysmon_pswitch will inform the user space powerd(8), which will possibly execute a script
     matching the type of the power switch.

FUNCTIONS

     After the sysmon_pswitch structure has been initialized, a new power switch device can be registered by using sysmon_pswitch_register().  The
     device can be detached from the framework by sysmon_pswitch_unregister().

     The sysmon_pswitch_event() is used to signal a new power switch event.  There are two possibilities for the value of event:

	   PSWITCH_EVENT_PRESSED     A button has been pressed, the lid has been closed, the AC adapter is off, etc.

	   PSWITCH_EVENT_RELEASED    A button has been released, the lid is open, the AC adapter is on, etc.

     The corresponding events in powerd(8) are pressed and released.

SEE ALSO

     powerd(8), pmf(9), sysmon_envsys(9), sysmon_taskq(9)

AUTHORS

     Jason R. Thorpe <thorpej@NetBSD.org>

BSD
								 January 26, 2010							       BSD

Linux and UNIX Man Pages

powerd(8) [freebsd man page]

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