Re: Question about cpufreq governors

From: DervishD
Date: Sat Jul 07 2007 - 06:06:58 EST


Hi Arjan :)

* Arjan van de Ven <arjan@xxxxxxxxxxxxx> dixit:
> On Fri, 2007-07-06 at 23:54 +0200, Jan Engelhardt wrote:
> > On Jul 6 2007 22:50, DervishD wrote:
> > >
> > > What I want to know is if I can choose "ondemand" governor instead
> > >of the recommended for AMD64, namely the "conservative" governor, since
> > >I will be switching between those two frequencies. I haven't found any
> > >information about my CPU regarding latency when switching between
> > >frequencies, so I don't know if I will be gaining anything using the
> > >"conservative" governor.
> > >
> > > Which governor is better suited for a CPU with only two fid's,
> > >"ondemand" or "conservative"?
> >
> > Depends on what you want. ondemand instantly switches when there is
> > something/nothing to do, while conservative uses a threshold (modeled upon
> > latency).
>
> for power saving, the ondemand behavior is better in general. However if
> you have a cpu that switches frequency very slowly, you may be better to
> not go as high quickly because going back down is then burning more
> power than needed potentially...

That's the problem: I want to use "ondemand" but I don't know if it
will work properly with my CPU because I don't know if my CPU switches
frequency fast or slow :( I can find that information, although the
Kconfig file for cpufreq says that AMD64 has latency problems (but I can
confirm that, I'm afraid).

Thanks for your answer :)

Raúl Núñez de Arenas Coronado

--
Linux Registered User 88736 | http://www.dervishd.net
It's my PC and I'll cry if I want to... RAmen!
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