AMD Core Performance Boost Patches Posted For P-State Linux Driver

[phoronix]

Phoronix: AMD Core Performance Boost Patches Posted For P-State Linux Driver

While not quite as exciting as yesterday's AMD XDNA driver publishing for Ryzen AI on Linux, a notable patch series out of AMD today on the Linux front is enabling AMD Core Performance Boost controls within their P-State CPU frequency scaling driver...

https://www.phoronix.com/news/AMD-Core-Perf-Boost-Linux

[Mitch]

Hopefully, this means we can disable the boost while in Active mode. It drives me nuts that we can't currently do that. On laptops, boost is usually not worth having on unless plugged in, and EPP bias isn't nearly enough to enforce efficiency goals IMO.

[cytomax55]

What is everyone using now for this?
Is active the recommended setting or are there pros and cons to each option?

[RealNC]

Can't you do that already by lowering the max clocks? For example on a 3700X with 3.6GHz base clock:

cpupower frequency-set -r -u 3.6GHz

[Mitch]

Can't you do that already by lowering the max clocks? For example on a 3700X with 3.6GHz base clock:

cpupower frequency-set -r -u 3.6GHz

I'd have to test it but as far as I understand, various PState modes expose various options. For example, in passive mode, you can use special governors like Conservative or OnDemand, but you cannot do that in Active mode.

And from what I recall, active doesn't let us put a cap on things.

[Mitch]

What is everyone using now for this?
Is active the recommended setting or are there pros and cons to each option?

Active is the default since... I think 6.4? And most distros prefer it that way. It's probably the best default, except if you have really unique processor behavior needs, but I still have some issues with how limited it is vs the other modes. IIRC, it does give great performance and energy savings usually.

[cytomax55]

I recently like 2 months ago did a fresh install of manjaro and I'm running the latest stable kernel and it still defaulted me to ACPI instead of pstate

[RealNC]

I'd have to test it but as far as I understand, various PState modes expose various options. For example, in passive mode, you can use special governors like Conservative or OnDemand, but you cannot do that in Active mode.

And from what I recall, active doesn't let us put a cap on things.

I use guided mode. I can cap it to as low as 550MHz. Active mode doesn't work at all for me (CPU is constantly stuck at 550MHz with no way to raise it.) Haven't tried passive (I don't know what the difference between passive and guided is, so I just chose guided at random and stuck with it.)

Active is the default since... I think 6.4? And most distros prefer it that way. It's probably the best default

Never worked here due to the problem I mention above.

[Anux]

Hopefully, this means we can disable the boost while in Active mode.

No, you are using the wrong mode. Active explicitly lets the CPU handle frequencies, what you want is guided.

See also TLP for an easier explanation: https://linrunner.de/tlp/settings/processor.html