powerd effectiveness

Bruno Ducrot ducrot at poupinou.org
Thu Jan 12 16:18:52 PST 2006


On Fri, Jan 13, 2006 at 10:27:37AM +1030, Daniel O'Connor wrote:
> On Fri, 13 Jan 2006 10:24, Bruno Ducrot wrote:
> > > Nearly all of the energy going into the CPU is disipated as heat.
> >
> > Of course.  But the goal of powerd is to reduce power comsuption with
> > nearly no visible impact on performance.  This imply that if the
> > runpercent is nearly 100%, then the processor will be put to full
> > frequency even though this can imply an overheat situation.
> > The role of acpi_thermal is to reduce frequency if the processor is
> > too hot, and this imply performance loss if runpercent is high.
> 
> Yes, but the original poster was wondering why their CPU temperature didn't go 
> down when the clock was (allegedly) very slow.

Maybe because the bus disconnect feature on the northbridge is not
enabled, and then the processor does not enter a low-power state upon
assertion of STPCLK# I think.

-- 
Bruno Ducrot

--  Which is worse:  ignorance or apathy?
--  Don't know.  Don't care.


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