Re: 2.6.25.x: Wrong CPU frequency (cpufreq table) with p4-clockmod

From: Henrique de Moraes Holschuh
Date: Mon Jun 02 2008 - 11:38:18 EST


On Sun, 01 Jun 2008, Roger Heflin wrote:
> From my testing, I believe the only thing that p4-clockmod does is forces
> an idle call when it could otherwise do work on an active process, so
> fullspeed and idle uses *EXACTLY* the same amount of power as p4-clockmod
> slower speed and idle (and therefore generates exactly the same amount of
> heat), the only power difference would be that if you were using
> p4-clockmod to slow down the cpu when it had an active running process
> (force the cpu to be idle a lot of the time even though it has work).

Indeed. And if we had a generic interface for throttling (ACPI
T-states-like) and frequency changes (ACPI P-states-like), we could just
move p4-clockmod to the throttling one (and NOT letting it register with
the frequency changes interface), and be done with it.

Do we have these interfaces?

--
"One disk to rule them all, One disk to find them. One disk to bring
them all and in the darkness grind them. In the Land of Redmond
where the shadows lie." -- The Silicon Valley Tarot
Henrique Holschuh
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