From: Denys Fedoryschenko <denys@visp.net.lb>
Organization: VISP
To: Matthew Garrett <mjg@redhat.com>
Subject: Re: 2.6.28 - 2.6.29-rc6-git5 regression, p4-clockmod/cpufreq probably
Date: Mon, 2 Mar 2009 18:15:56 +0200
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Cc: linux-kernel@vger.kernel.org, "Rafael J. Wysocki" <rjw@sisk.pl>,
       cpufreq@vger.kernel.org, davej@redhat.com
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On Monday 02 March 2009 18:06:59 Matthew Garrett wrote:
> On Mon, Mar 02, 2009 at 05:04:59PM +0200, Denys Fedoryschenko wrote:
> > On 2.6.29-rc6 (git5 tested also) also shown in dmesg as available, but i
> > can't change anything.
>
> That's deliberate. p4-clockmod is for thermal management, not clock
> control (since it doesn't actually do any of that)
I know very well it is just throttling, and not real CPU power management.
At the end it does job.

In my case i used it for testing on "virtual" 113 Mhz video encoding to find 
out bottleneck on ffmpeg and to compare performance with Blackfin.

In another case it helps me to limit current from battery(i have custom power 
supply solution), so battery will lasts longer (on spikes, if it uses full 
CPU power at 900 Mhz, voltage dropping (specially on last "drops of battery 
life), and protection unit disconnecting laptop. Throttling helping to 
prevent this.

Actually i am not asking if it nice or not, just if there is feature which is 
not working.
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