User:Bjordan/Chris Power MGMT
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?
- me: We could collect some data of frequency of checks in order to catch the most mesh networks?
Joe: Hibernation mode?
- Chris: waking up, what hardware will there be?
- Chris: disc space tradeoff makes it hard to hibernate
- Better idleness detection
Daniel: in wireless, power-saving modes in AP
- If you have AP, large schools have APs
- Chris: OLPC supports that mode
- We may not be doing this, follow up
Michael - What needs to be done? How can we help?
- Activities doing a good job vs. bad job of supporting power management
- Look at top - CPU usage
- Look at vmstat (how many context switches are happening?)
- Timer list using powertop wikipedia
- Needs dynamic ticks ext on kernel
- /proc/timer_list and /proc/timer_stats
- Could be thrown into tinderbox
- Provide powertop in joyride and/or a GUI for powertop
- Pie menu in main screen as memory usage by each activity
- Also power usage pie
- Accumulated power register
- Modify Sugar to collect power usage data
- Chat with Scott on how to get data on power usage
- Also power usage pie
What other data can activities be providing? Crashes, errors, etc.
Dynamic heuristic gathering / development
- Activity specific?
Pie menu is nice because it shows all users how much power is being used... without Chris having to yell at developers
Even when off -- embedded controller sits there and waits for power button to be turned on
Why is 708 not waking up on keyboard presses?
- Lid open -- error, screen on, then back off
Chris has Beamer PDF