Core i9-9900 power saveing


x-dast

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5 minutes ago, John_M said:

If you want to use the plugin you need to keep it installed.

Thats perfectly clear. I want the cpu throttle down without any additional plugin. And the only way i see at the moment is to disable the pstat driver. Sad that this problem comes up again after years.  

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  • 2 weeks later...

After further testing, it seems that there are CPU driver problems in Unraid (apparently with the CPU c-state and p-state).

 

Unraid + 1 SSD running + all HDD in standby: 80-90W idle
Unraid + 3 SSD running + all HDD in standby + Windows VM running (6 cores and RTX2080 passthrought): 40-50W idle

 

I hope that this will be fixed in an upcoming update with the 5.x kernel.

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Ok, problem seems to be the RTX2080. If I remove the RTX2080, the power consumption drops down to 40-50W. I think that Unraid does not set the GPU in powersave and therefore still always runs in performance mode. Windows in the VM sets the RTX2080 correctly in powersave. I hope this will be fixed in a next update, so that the VM doesn't always have to run.

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On 2/1/2020 at 1:14 AM, x-dast said:

Ok, problem seems to be the RTX2080. If I remove the RTX2080, the power consumption drops down to 40-50W. I think that Unraid does not set the GPU in powersave and therefore still always runs in performance mode. Windows in the VM sets the RTX2080 correctly in powersave. I hope this will be fixed in a next update, so that the VM doesn't always have to run.

A big reason Windows can idle much lower by default is because it's a GUI first system, with a driver model that demands GPU makers include every possible state available for Windows to use, usually even before the first visual element appears on screen.

 

Something that might gain similar results is to download a recent LibreELEC ISO and make a VM passing through your GPU and Audio to it.  Setup power save in the GUI to sleep the screen after 1min.  Disable any background audio settings. Enable SSH and then wait for the display to sleep.  SSH in and issue a command to STOP the Kodi GUI, which reduces this VM CPU cycles to bare minimum now.

 

These are just a few things, but you get the idea.  When you need to use the GPU in another VM, you'll have to shutdown the LibreELEC VM by SSHing in, issue a CONTINUE to the Kodi GUI, then after a few seconds issue a HALT to the LibreELEC VM.

 

This might not work well in every configuration, but it's a fast way to test as a possible option, without having to devote several GBs of RAM and constantly writing to storage just for a Windows VM.

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  • 1 month later...

I have the same problem. Found that intel_pstate driver is very sensible. If you run popular watch command it simply shows wrong results:
 

watch "grep 'cpu MHz' /proc/cpuinfo"
cpu MHz         : 4742.255
cpu MHz         : 4480.885
cpu MHz         : 4451.161
cpu MHz         : 4420.211
cpu MHz         : 4473.812
cpu MHz         : 4423.951
cpu MHz         : 4432.021
cpu MHz         : 4477.743
cpu MHz         : 4558.370
cpu MHz         : 4413.524
cpu MHz         : 4425.724
cpu MHz         : 4484.005
cpu MHz         : 4425.530
cpu MHz         : 4403.425
cpu MHz         : 4437.033
cpu MHz         : 4382.428

But if you decrease the update interval the results are much better: 

watch -n 0.3 "grep 'cpu MHz' /proc/cpuinfo"

cpu MHz         : 1686.816
cpu MHz         : 1713.529
cpu MHz         : 992.136
cpu MHz         : 971.635
cpu MHz         : 1724.956
cpu MHz         : 4800.423
cpu MHz         : 3784.639
cpu MHz         : 4902.354
cpu MHz         : 967.030
cpu MHz         : 1059.654
cpu MHz         : 1674.691
cpu MHz         : 1738.267
cpu MHz         : 2040.228
cpu MHz         : 1502.640
cpu MHz         : 889.176
cpu MHz         : 838.754

I guess, watch command immediately wakes up the CPU showing high frequency.

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39 minutes ago, rl2664 said:

Don´t work for me. CPU freq stays at boost freq 3.8 Ghz. Only pstat driver disable helps.

Did you also trigger "Performance" -> "Power Save" in Tips and Tweaks? Anyway, I just continue to measure performance and looks like SMB works better with ACPI driver. I will stay with disabled pstates as well. At least until kernel 5.

Currently, slow SMB write speeds and CPU power issues only major problems stopping me from switching to unRAID.

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