Problem : Run all core on minimum CPU frequency on Intel pstate driver on ubuntu 14.
cpupower frequency-set --governor performance --max 1300MHz
I am trying to run my cpu cores on different constant frequencies. For this i have chosen performance governor. I have set all of my scaling max frequency range from 1.2GHz to 1.3GHz
# cat /sys/devices/system/cpu/cpu*/cpufreq/scaling_max_freq
1300000
1300000
1300000
1300000
1300000
1300000
1300000
1300000
1300000
1300000
1300000
1300000
1300000
1300000
1300000
1300000
1300000
1300000
1300000
1300000
1300000
1300000
1300000
1300000
1300000
1300000
1300000
1300000
But my limits get overridden and i have no idea why. I tried going through alot of similar problems and could not find anything conclusive.
cpufrequtils 008: cpufreq-info (C) Dominik Brodowski 2004-2009
Report errors and bugs to [email protected], please.
analyzing CPU 0:
driver: intel_pstate
CPUs which run at the same hardware frequency: 0
CPUs which need to have their frequency coordinated by software: 0
maximum transition latency: 0.97 ms.
hardware limits: 1.20 GHz - 3.30 GHz
available cpufreq governors: performance, powersave
current policy: frequency should be within 1.20 GHz and 1.30 GHz.
The governor "performance" may decide which speed to use
within this range.
current CPU frequency is 1.20 GHz (asserted by call to hardware).
analyzing CPU 1:
driver: intel_pstate
CPUs which run at the same hardware frequency: 1
CPUs which need to have their frequency coordinated by software: 1
maximum transition latency: 0.97 ms.
hardware limits: 1.20 GHz - 3.30 GHz
available cpufreq governors: performance, powersave
current policy: frequency should be within 1.20 GHz and 1.30 GHz.
The governor "performance" may decide which speed to use
within this range.
current CPU frequency is 1.20 GHz (asserted by call to hardware).
analyzing CPU 2:
driver: intel_pstate
CPUs which run at the same hardware frequency: 2
CPUs which need to have their frequency coordinated by software: 2
maximum transition latency: 0.97 ms.
hardware limits: 1.20 GHz - 3.30 GHz
available cpufreq governors: performance, powersave
current policy: frequency should be within 1.20 GHz and 1.30 GHz.
The governor "performance" may decide which speed to use
within this range.
current CPU frequency is 1.20 GHz (asserted by call to hardware).
I think these hardware limitations are imposed (hardware limits: 1.20 GHz - 3.30 GHz) but i donot know how to change these limitations. The bios_limit feature is available in acpi driver but not intel pstate.
Also, i spent ALOT of time on disabling intel pstate on my ubuntu 14 but it does not revert back to acpi. There is some issue in my kernel. I say this because on other machines i am able to revert back to the old kernel. So acpi is not an option.
Does anyone know why these limits are not enforced?
As you can see in the image , most cores go way beyond (29GHz) my enforced limit of 1.3GHz
https://ibb.co/hOmVfU