Re: cpufreq and p4 prescott

From: clemens kurtenbach
Date: Thu May 13 2004 - 02:23:20 EST


[ck@holodeck:cpufreq] cat /proc/cpuinfo | grep Mhz
cpu MHz : 2807.131
cpu MHz : 2807.131

The cpu MHz entry in /proc/cpuinfo is the same for all CPUs, and no reliable
source to detect the current cpu frequency anyway. Use

i thought this because on my ibook i can see different MHz
entry's when cpudyn changes the frequence.

/sys/devices/system/cpu/cpu0/scaling_cur_freq or even cpuinfo_cur_freq for
that.[*] So p4-clockmod-throttling does work on your p4 prescott.


[*] Available in 2.6.7, hopefully, if Linus merges the latest cpufreq-bk
tree from Dave. It'll be in the next -mm release, though.

o.k, when i understand you right p4-clockmod-throttling _is working_
on my system, but i can't see this in /sys until Dave Jones
patches are includet. So i patched my 2.6.6 kernel with

Now cpuinfo_cur_freq and scaling_cur_freq show changing entry's
when eg powernowd handles the frequence.

The reason why i want to throttle down my prescott is the heat.
Strange is that when the frequence is changed to 350MHz
(after 30min running with 2.8GHz), neither the CPU&System temperature
nor tools that calculate the CPU speed (like gkrellm-x86info)
show a difference to 2.8GHz. All voltages on my system are the
same with 350MHz/2.8GHz, too.

So i'm not sure if throttling does work until now?

moqua [at]
moqua [at]

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