How to measure current hardware frequency

[SPann1]

I have been performing some experiments to understand the power distribution between CPU and GPU power planes while applying RAPL power limit. I see that the power usage in both these power planes get throttled to stay within the power limit.

But I wanted to measure the frequency at which CPUs and GPU are running. The operating system (Linux in my case) does not expose the current operating frequency. The sysfs location given below only reports the system set frequency but it does not report the current hardware frequency.

CPU: /sys/devices/system/cpu/cpu*/cpufreq/scaling_setspeed

GPU: /sys/class/drm/card0/gt_cur_freq_mhz

How do I measure the current hardware frequency for both CPUs and GPU - Are there any MSRs exposing these values?

[EstebanA_C_Intel]

Hello Sankar:

Thank you for contacting the Intel Communities.

Please check this article related to the power power consumption on the Linux* operating system.

https://software.intel.com/en-us/blogs/2013/06/18/measuring-application-power-consumption-on-linux-operating-system Measuring application power consumption on the Linux* operating system | Intel® Developer Zone

This would assist you to monitor the consumption in your system.

Regarding the GPU power consumption, the manufacturer of your GPU may have an application for that, my recommendation would be to check that with them directly.

Regards,

Esteban C

[SPann1]

Thanks for the info. By GPU, I meant the on-chip gpu - Intel HD Graphics. I wanted a way to measure the on-chip GPU frequency.

[EstebanA_C_Intel]

Hello Sankar:

Have you tried with different third party monitoring software? They may have this information available in their "power checks".

The power consumption would depend on the usage of the device being monitored, it may go up or down depending on the task it is performing, which would make the measurement of this difficult. There is were the monitoring software would assist you.

Regards,

Esteban C