Re: Power Management framework proposal



example 1: a laptop screen

mode capacity power description
0 0 0 off
1 100 100 full brightness
2 70 60 half power to the backlight
3 50 35 quarter power to the backlight
4 30 25 eighth power to the backlight
5 5 10 backlight off.

example 2: a front-panel display on a server (no variable backlight
control)

mode capacity power description
0 0 0 off
1 100 100 backlight on
2 50 10 backlight off


the problem is: the person who SETS these needs to know what they mean.
And the side that implements these needs to translate them as well...

that's two translations, and information is lost in the abstract number
in the middle that doesn't mean anything

if you don't want to make the shift with cpufreq, that's fine. it
sounds
like you are at least 90% of the way there anyway, it's not that big
a
deal, but do you think that there's value in replacing the current
ad-hoc
approach with something more structured (even if it's not this
proposal)?

as someone who wrote (part of) a power policy manager; sorry but you
take away information I need, and in addition the different API's are
absolutely no big deal.

--
if you want to mail me at work (you don't), use arjan (at) linux.intel.com
Test the interaction between Linux and your BIOS via http://www.linuxfirmwarekit.org

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