[SOLVED] How to reduce power consumption?

[thinhnguyen]

I use a computer with 2 Xeon Gold 6140 CPUs to install proxmox. When the machine is idle, I check the frequency and it is running at the base frequency (2.3 Ghz) for all cores. The driver being used is intel_pstate. Governor mode is "performance".

- When I switch the governor to "powersave" mode, the operating frequency is limited to the base frequency (2.3 Ghz) and cannot be increased any higher, which slow down the operation of the system. Because the maximum frequency can be up to 3.7 Ghz

- When I switch the governor to "performance" mode the minimum operating frequency is the base frequency (2.3 Ghz) and it can't be any lower, I think it will increase the power consumption.

I would like the frequency to scale more flexibly according to the hardware's limits (1Ghz - 3.7Ghz) depending on the task it is performing. Is there any way to do this? or if this is CPU specific behavior please explain to me why it is so?

Thank you everyone.

[Edit]
The behavior above is noticed when using the command "cpufreq-info". But when I switch to using "powertop" command to check the CPU frequency, the operation of the intel_pstate driver is exactly as its theory. so I ended up using the intel_pstate driver and adjusting the governor to "powersave".

 

[Nuke Bloodaxe]

Okay, this is interesting, I think you'll find Intel's official documentation quite helpful:
https://www.intel.com/content/www/u...e/kvm-tuning-guide-on-xeon-based-systems.html

Let me know how things go Oh, and for the governor you're after: ondemand

 

[thinhnguyen]

Okay, this is interesting, I think you'll find Intel's official documentation quite helpful:
https://www.intel.com/content/www/u...e/kvm-tuning-guide-on-xeon-based-systems.html

Let me know how things go Oh, and for the governor you're after: ondemand

It seems that the governor "ondemand" is unavailable in my computer. This is the output of available scaling governor:

$ cat /sys/devices/system/cpu/cpu*/cpufreq/scaling_available_governors

It returns 2 modes as below:

performance
powersave

 

[Nuke Bloodaxe]

While I think of it, are you running a scavenger board from China?

 

[thinhnguyen]

While I think of it, are you running a scavenger board from China?

No! the computer is DELL Precision 7820 Fix work station. The CPU is Intel Xeon Gold 6140 (Skylake). I used ISO file from offical website to install proxmox. I can guarantee this computer is a real machine not a fake.

 

[Nuke Bloodaxe]

For some more fine-grained control: https://www.kernel.org/doc/html/v4.12/admin-guide/pm/intel_pstate.html

 

[Nuke Bloodaxe]

No! the computer is DELL Precision 7820 Fix work station. The CPU is Intel Xeon Gold 6140 (Skylake). I used ISO file from offical website to install proxmox. I can guarantee this computer is a real machine not a fake.

Only asking No offence intended. Some quite unusual pieces of kit are out there, so all bases need to be checked. The prior link I gave should be quite helpful.

 

[thinhnguyen]

Only asking No offence intended. Some quite unusual pieces of kit are out there, so all bases need to be checked. The prior link I gave should be quite helpful.

I get it! I try to be as informative and clear as possible for help. I will study the document you sent.

 

[neail]

I get it! I try to be as informative and clear as possible for help. I will study the document you sent.

Hey man, a dumb question but have you checked for the latest BIOS (firmware)!

 

[sb-jw]

Dell systems usually have performance profiles stored in the BIOS. Look at what it says. As far as I know, corresponding states are deactivated if, for example: Performance is set. If you want to save electricity, DAPC might be a state for you.
See also: https://infohub.delltechnologies.co...oweredge-system-profile-set-to-performance-1/