[PATCH] powerpc: Enable DEEPNAP power savings mode on 970MP
mb at bu3sch.de
Fri Oct 6 05:25:15 EST 2006
On Thursday 05 October 2006 06:41, Olof Johansson wrote:
> Without this patch, on an idle system I get:
> Total: 103.8W
> With this patch:
> Total: 65.0W
> If I lower HZ to 100, I can get it as low as:
> Total: 60.2W
> Another (older) Quad G5 went from 54W to 39W at HZ=250.
> Coming back out of Deep Nap takes 40-70 cycles longer than coming back
> from just Nap (which already takes quite a while). I don't think it'll
> be a performance issue (interrupt latency on an idle system), but in
> case someone does measurements feel free to report them.
> Signed-off-by: Olof Johansson <olof at lixom.net>
Acked-by: Michael Buesch <mb at bu3sch.de>
I am running DEEPNAP on my Quad since quite some time and I
did not see any problems.
It saves quite a bit of power (I think it was about 20W for me when
I measured it)
That's really worth it.
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