OpenSuSE 10.2 on a T60 - CPU Freq Scaling not working

[Harryc]

Anyone have this working? CPU Freq. stays at 2GHz on the machine in my sig running OpenSuSE 10.2. I tried the various modes in kpowersave, no change. Both CPU's idle at or close to 0% utilization so it should kick in ...

laptop:/home/harryc/# cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_available_governors
conservative ondemand userspace powersave performance

laptop:/home/harryc/ # cat /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_max_freq
2000000
laptop:/home/harryc/ # cat /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_min_freq
1000000

or maybe it is working but I am looking at this the wrong way? gkrellm says 2000MHz, but maybe that is cumulative across both processors at 1000MHz?

laptop:/home/harryc/downloads/downloads # cat /proc/cpu
cat: /proc/cpu: No such file or directory
laptop:/home/harryc/downloads/downloads # cat /proc/cpuinfo
processor : 0
vendor_id : GenuineIntel
cpu family : 6
model : 14
model name : Intel(R) Core(TM) Duo CPU T2500 @ 2.00GHz
stepping : 12
cpu MHz : 1000.000
cache size : 2048 KB
physical id : 0
siblings : 2
core id : 0
cpu cores : 2
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 10
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx constant_tsc pni monitor vmx est tm2 xtpr
bogomips : 3994.35

processor : 1
vendor_id : GenuineIntel
cpu family : 6
model : 14
model name : Intel(R) Core(TM) Duo CPU T2500 @ 2.00GHz
stepping : 12
cpu MHz : 1000.000
cache size : 2048 KB
physical id : 0
siblings : 2
core id : 1
cpu cores : 2
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 10
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx constant_tsc pni monitor vmx est tm2 xtpr
bogomips : 3990.11

Also, it is possible to do GPU scaling on Linux?

[dummkopf]

cpufreq-info will tell you everything you need to know. If it's installed, of course. Do not know a thing about GUI-oriented distros, I'm very limited to CLI.

[ctrler]

Use cpufreq-info to check what governor you are using.
If you don't have cpufreq-info you can view the info on /sys.

On my system i get this output:

[root@neptuno ctrler]# cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
ondemand
[root@neptuno ctrler]# cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_available_governors
ondemand performance
[root@neptuno ctrler]# cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq
800000

As you can see I'm using the ondemand governor.
To use it you have to load the cpufreq_ondemand and the acpi-cpufreq modules.

To change the current governor just issue:
[root@neptuno ctrler]# cpufreq-set -g ondemand
or
[root@neptuno ctrler]# echo ondemand > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor

Hope I could help.

[jamesqf]

"CPU Freq. stays at 2GHz on the machine in my sig running OpenSuSE 10.2. I tried the various modes in kpowersave, no change. Both CPU's idle at or close to 0% utilization so it should kick in ..."

If what I read is correct, with newer CPUs & kernels frequency scaling is usually not the best way to save power. It's better to use the "ondemand" governor, which puts the processor in deep sleep when there's no work to do, then wakes up to do work at top speed so it can go back to sleep sooner.

There's discussion and a useful tool called powertop at this site:

http://www.linuxpowertop.org/powertop.php

[lightweight]

Also, it appears much of kernel development is focussed on increasing battery life in Linux. 2.6.21+ has been very good to me and offers dynticks, which had greater effect without cpufreqd than 2.6.18 had with cpufreqd and no dynticks. YMMV of course.