kernel 6.5 amd_pstate=passive schedutil governor

[Wolvez]

I'm on an AMD EPYC Rome CPU
Since PVE7 and kernel 5.15 I have been running the schedutil governor(!LIKE YOU'RE NOT SUPPOSED TO!) since it gave me a 10-15watt power reduction. After upgrading to PVE8 and kernel 6.2 I added amd_pstate=passive to the kernel command line to take advantage of the newer power saving features. I didn't notice any change in performance or power usage.
With the update to PVE8.1 and kernel 6.5 performance is terrible. My one Windows VM that I run sporadically felt like it was running on a 5400 HDD with Windows update and a virus scan running. Setting the governor to performance fixed the issue.
So apparently don't do dumb stuff like me. And if you did do dumb stuff like me, that is probably what your problem is.

 

[Ernst T.]

added amd_pstate=passive to the kernel command line

Have you tried "amd_pstate=active" with 6.5 Kernel? Works really good on my Ryzen System.

 

[aabbccdd]

Cool. I have been waiting for the 6.5 kernel series to become available in Proxmox for the amd-pstate drivers. Will test and report back.

 

[leesteken]

amd_pstate=guided appears to work fine with schedutil (and CPPC enabled in BIOS): https://forum.proxmox.com/threads/amd-pstate-driver-steps-and-discussion.118873/post-610243

 

[Wolvez]

Yea after I posted I switched to amd_pstate=active. There didn't seem to be a difference between the EPP performance or powersave governors. Today I enabled CPPC and a couple of other options in the BIOS. Now there seems to be a difference between the two. The performance governor is more spiky power wise. More importantly the powersave governor doesn't cripple performance like amd_pstate=passive and schedutil governor did.

So if you are on kernel 6.5 and want to save on power, amd_pstate=active and the powersave governor is probably the way to go. At least based on my little bit of testing.

 

[aabbccdd]

Also related: https://forum.proxmox.com/threads/amd-pstate-driver-steps-and-discussion.118873/page-2#post-610939