On 1/01/2011 1:49 AM, 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]:
---
Using Frequency Scaling Governors
You can get a list of available governors with (as root):
# cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_available_governors
conservative ondemand powersave userspace performance
Note: If the governors are compiled as modules, load them first:
# modprobe cpufreq_performance cpufreq_ondemand cpufreq_conservative
cpufreq_powersave cpufreq_userspace
Now we set our governor: What is our current governor?
# cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
userspace
Set new governor and watch if it has changed
# echo conservative> /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
# cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
conservative
Congrats! Your governor is active.
You may set the governor in your rc.local, to make it used on every boot.
---
Richard
[1]
http://www.thinkwiki.org/wiki/How_to_make_use_of_Dynamic_Frequency_Scaling
Interestingly enough, I tried setting the governor to userspace. Now
when I run /etc/init.d/cpuspeed start, I can see the CPU speed scale. It
isn't as quick as the kernel ondemand governor, but it does scale up and
down with load.
This makes me quite curious.
--
Steven Haigh
Email: netwiz(a)crc.id.au
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