Today I updated to the new stable kernel 3.10.0 (openSUSE Kernel repo for 12.3 [1]) and since then the automated CPU frequency throttling does not work any longer. It still works perfectly fine with the 3.9 kernel series from the same repository (until yesterday available there).
Now the default behaviour is, that the turbo mode of my Intel i7 3520M CPU is on, resulting in an idle frequency of 3.6 GHz.
I managed to switch off turbo mode manually by running as su
echo -n 1 > /sys/devices/system/cpu/intel_pstate/no_turbo
resulting in an idle frequency of 2.9GHz.
I’ve tried enabling the ‘powersave’ governor with either cpufreq-set and cpupower. Without any effect.
Is it a known bug of the 3.10. kernel or is some configuration of my system messed up? I haven’t changed anything except updating my kernel from 3.9.8-1.gf3348a8-desktop to 3.10.0-1.g3dcd746-desktop this morning.
[1]: Index of /repositories/Kernel:/stable/standard
So I played around a little bit. I deinstalled cpufrequ-utils and cpupower (the userspace scaler). This did not had any effect. Then I added intel_pstate=disable
to the kernel command line resulting in the old, well-known behaviour. I’ll try finding some help on the kernel mailinglist. Either it’s a bug in the intel_pstate module or some other of my BIOS or system settings are conflicting with it.
Been having similar temperature problems with an intel core i5 540m running kernel 3.10 in 12.3. Booting from a live cd dropped the temperature by 10 degrees, but booting the shipped 3.7 kernel in 12.3 didn’t have the same effect.
I was under the impression that changes were only going to affect Sandy Bridge and later processors. I’m not really clear from your description either
I’ve been looking around and it seems my problem has been longstanding but only now as my laptop has aged has it become a problem. So, basically it’s never been fixed since kernel 3.5~.
If you would like to play around with the new pstate, you might try the Thermal Power Manager Daemon:
Background:
Linux Thermal Daemon Monitors and Controls Temperature in Tablets, Laptops | Linux.com
https://01.org/linux-thermal-daemon/documentation/introduction-thermal-daemon
Code:
https://github.com/01org/thermal_daemon
Suse build notes:
Using linux-glibc-devel 3.7, for errno.h to be found I had to symlink
ln -s /usr/include/asm-generic/ /usr/include/asm
Usage notes and test script in src dir