10 Powersave Events

Events are triggered from the daemon when Hardware changes are recognised or user requests have been made.

Have a look into /etc/powersave/events where you may want to change the default behaviour how events get processed.

The syntax is: EVENT="action1 action2 action3 ..."

Events are triggered e.g. when:

• power/sleep button presses and the lid closing/opening.
• battery levels are exceeded
• the power source changes (AC/Battery)
• temperature limits are reached
• the user requests a suspend/standby sleeping state
• the machine resumes from a suspend/standby sleeping state
• the daemon is stopped/started
• the user manually requests a power save policy, so called scheme change
• the CPU usage was under a certain level for a specific time (configurable in cpufreq conf file)
• Any non thermal, battery, ac or button ACPI event had happend

If an event happens, the configured actions for this event are processed from left to right.

There are internal (processed from the daemon internally) and external actions (executed scripts located in /usr/lib/powersave/scripts) that can be assigned to each event.

Internal actions (name is reserved, scripts must not be named like that) currently are:

• ignore (do nothing)
• throttle (throttle cpu(s) if throttling is enabled in this scheme)
• dethrottle (unthrottle cpu(s))
• reread_cpu_capabilities
  (Trigger reevaluation of usable CPU speeds. There are machines, that cannot run on full speed when on battery. This internal event causes a reevaluation of which speeds are available. Usually only makes sense in acadapter.*-events).
• suspend_to_disk (Trigger the global.suspend2disk event)
• suspend_to_ram (Trigger the global.suspend2ram event)
• standby (Trigger the global.standby event)
• do_suspend_to_disk
  (Actually tell kernel to do a suspend-to-disk. Should only be used from a global.suspend2disk event)
• do_suspend_to_ram (see do_suspend_to_disk)
• do_standby (see do_suspend_to_disk)

Example: put EVENT_OTHER="debug_events" into /etc/powersave/events to debug the hotkey events on some ASUS notebooks (the asus_acpi module has to be loaded) and watch /var/log/messages for the output of the debug_events script..

See the next chapter (Scripts) how to write your own scripts for events.