RFC: powerd Patch & proposed future changes

[Rene Schickbauer]

Hi!

> I think this is a very nice idea, especially the TFT backlight part. It
> also might be useful to adjust the WiFi transmit power level according
> to battery state. That can also save some power, especially on
> portables.

Yes, changing the transmit power would be possible. Although adjusting the
transmit power via script on a *mobile* computer is likely to get the user
offline rather quickly.

On the other hand, powerd would just run a script. This script could start a
user-written daemon to continually adjust power level.. and when ac is
plugged in again, the script kills that daemon. I sincerely doubt that would
save you any amount of power worth mentioning, though but may give you
additional troubles. But maybe you could restrict an a/b/g card to b/g or a
and thus save some power.

Some laptops let you power down the normal (cabled) network adapter. When
your out of reach for AC power, you're very unlikely lugging a network cable
around the building. Also, you may power down/unload inbuild audio, webcam,
bluetooth, modem, serial port etc. If you're desperate, disallowing CDROM 
and SWAP operation may save you a ton of power, too.

As i said, with user scripting triggered by powerd state changes, you could
get *really* creative (like temporarly halting any mencoder and ffmpeg
process while on battery power ;-).

LLAP & LG
Rene Schickbauer
-- 
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