[mythtv-users] Cool'n'Quiet setup help

[John Finlay]

Allen Edwards wrote:
>
>
> On Sun, Feb 8, 2009 at 5:03 PM, John Finlay <finlay at moeraki.com 
> <mailto:finlay at moeraki.com>> wrote:
>
>     Allen Edwards wrote:
>
>         I have an AMD 5400+ running Mythbuntu 8.10.  I would like to
>         run cool'n'quiet to cut the cpu temp and power.  I enabled it
>         in the BIOS and the results were unsatisfactory.  The program
>         would stutter.  I could see that the cpu was running at 1GHz
>         during program mode and that wasn't enough.
>
>         What I want to do is have the CPU at a low clock frequency but
>         when there is basically any activity at all, have it go to
>         100% clock.  For example, right now the CPU is at .6%.  It
>         would be nice if the clock was at a minimum.  But if the cpu
>         goes above, say 2%?, I want the CPU to go to max clock so it
>         wont stutter.
>
>         I see instructions on the net how to do this but they are 3
>         years old and experience has thought me that following
>         instructions like this causes a half day work getting the
>         system working again because the instructions were for an
>         older system.
>
>         So, can anyone with a system like mine who has enabled
>         cool'n'quiet and understands what I am saying help me out?
>
>         Allen
>
>     This uses the cpufreq module which uses the threshold (% cpu) in:
>
>     /sys/devices/system/cpu/cpu0/cpufreq/ondemand/up_threshold
>
>     As root you can change this e.g.:
>
>     echo -n 10 >
>     /sys/devices/system/cpu/cpu0/cpufreq/ondemand/up_threshold
>
>     Other params in /sys/devices/system/cpu/cpu0/cpufreq can be
>     changed as well:
>
>     scaling_max_freq
>     scaling_min_freq
>     ondemand/ignore_nice_load
>
>     If using Ubuntu you can set params on boot in the
>     /etc/init.d/powernowd file. Add in the use_ondemand() function
>     something like:
>
>               if [ -f $x"cpufreq/ondemand/up_threshold" ]; then
>                   echo -n 20 > $x"cpufreq/ondemand/up_threshold"
>               fi
>
>
>     If using Fedora the /etc/sysconfig/cpuspeed file allows you to
>     tweak things.
>
>     John
>
>
> I apologize if this is a stupid question but I don't have a file 
> called up_threshold on my system.  I do have powernowd but 
> not cpufreq.  I can find online docs for powernowd  but again they are 
> many years old and I have to assume out of date.
>
> Allen
>
>
Sounds like you are not loading the kernel module that provides cpufreq.

Install the powernowd package if it isn't already there (I think it's 
there by default). On my systems the powernowd rc links load the 
required modules but don't start the powernowd daemon. Check to see that 
both the powernod and powernod.early rc links are setup.

Here's the way to do it without the powernowd package:

http://ubuntuforums.org/showthread.php?t=248867)

A quick test is to:

lsmod | grep powernow-k8
lsmod|grep cpufreq

to check if the modules are loaded. If not you can :

modprobe powernow-k8
modprobe cpufreq_ondemand

to load them. Then the /sys/devices/system/cpu/cpu0/cpufreq directory 
should exist.

John