[CentOS] centos 7: trouble setting the ondemand governor

Wed Jul 16 20:35:56 UTC 2014
Corey Hickey <bugfood-ml at fatooh.org>

Hi,

The default "stop" action for the cpupower service seems to be to set
the ondemand governor, but this fails. I can reproduce the issue
directly by running cpupower:

$ sudo cpupower frequency-set -g ondemand
Setting cpu: 0
Error setting new values. Common errors:
- Do you have proper administration rights? (super-user?)
- Is the governor you requested available and modprobed?
- Trying to set an invalid policy?
- Trying to set a specific frequency, but userspace governor is not available,
   for example because of hardware which cannot be set to a specific frequency
   or because the userspace governor isn't loaded?


The ondemand and powersave governors work ok (powersave is the default
when the host boots).

Some diagnosis:

$ grep ONDEMAND /boot/config-3.10.0-123.el7.x86_64 
CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND=y
CONFIG_CPU_FREQ_GOV_ONDEMAND=y
$ cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_available_governors
performance powersave

So apparently the kernel is configured to support ondemand, but it is
not available. I know that the hardware and BIOS are capable of it--in
fact, I just rebuilt the host on centos 6.5 to verify, and ondemand
works fine. Also, I don't know a reason why powersave would work but
ondemand would not, hardware-wise.

CPU: Intel E5-2670
System: SGI C1110-RP6

I'd appreciate any tips. I don't know if I've found a bug or if I'm
doing something wrong.

Thanks,
Corey