F14 cpuspeed / ondemand broken?

drago01 drago01 at gmail.com
Mon Jan 3 13:28:52 UTC 2011

On Mon, Jan 3, 2011 at 2:08 PM, Adam Williamson <awilliam at redhat.com> wrote:
> On Fri, 2010-12-31 at 08:49 -0600, Richard Shaw wrote:
>> I wish I could find the site where I got this information as my
>> recollection of it is a bit hazy but part of your problem may be that
>> the p4-clockmod and ondemand are more or less incompatible. I remember
>> reading something on kerneltrap or something. Basically the latency of
>> changing frequencies are so bad with p4-clockmod that ondemand gives
>> up on it or something like that. I think I could force it to work on
>> my Celeron based EEEPC by manually setting the governor something like
>> this[1]:
> yeah, I recall p4-clockmod being called out as problematic in several
> ways by some kernel dev or other, but like you I can't recall the
> details :/
> on my system which wants to use p4-clockmod, I just blacklist it and run
> full steam ahead all the time.

And uses _less_ power while doing so.

See: http://codemonkey.org.uk/2009/01/18/forthcoming-p4clockmod/

In short p4-clockmode is broken by design, don't use it.

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