powerd adaptive mode latching

Dag-Erling Smørgrav des at des.no
Thu Jan 17 02:15:11 PST 2008

"Daniel O'Connor" <doconnor at gsoft.com.au> writes:
> One problem with it is that it lags behind actual usage by a few
> seconds (presumably averaging it).

It is based on the (didle/dt) / (dtotal/dt) fraction computed from
kern.cp_time, which can take a while to ramp up.  This is not easily
seen in a cursory reading of the code, as the fraction is computed in a
very roundabout way.

> Turning the LCD off saves about 4W too.

Hmm, it would be interesting to experiment with varying backlight
brightness based on system load :)

Dag-Erling Smørgrav - des at des.no

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