User:Bjordan/Chris Power MGMT

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Control of power --> transmitter? vs. using repeater

OHM - "Open Hardware Manager" by Richard Hughes

Useful debugging tools for power management:

ohmd --verbose --no-daemon
lsohm # ohm's ideas of what state things are in
lshal # all things hal knows about status of battery, lid, etc
lshal --monitor # realtime, HW events broadcasted to ohm

Wakeup events: (all policy decisions go through ohm)

  • Suspend mode - in Joyride
  • Sleep mode - in Joyride
    • Wakeup doesn't work well in 703

Idleness detection: (don't want to turn off during an update)

  • Mouse/keyboard idle for 60s?
  • CPU also idle? # might be doing compile
  • Has dbus signal inhibited suspend? or /etc/ohm/inhibit-idle-suspend
  • Have tty1 or tty2 been used recently? (printing to or typing to)
  • Are audio/camera devices in use? # Not implemented. Record, distance.
  • DISTANCE: CHIRP ... idle for 10s ... CHIRP, etc. Not necessarily idle.

In linux: CPU-idle - different states a CPU can be in

Power breakdown: 703

  • RAM 700mW DCON 200mW EC 100mW LCD 300mW CPU 1W-3W Backlight
  • Maybe make a graph of progress?

Francesca: Mesh/antenna off? Joe: Hibernation mode?