How does linux scheduler work with AMD V-Cache?

Software & Operating Systems Linux
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I’m considering an upgrade to my current AM4 system, and have a real hard time deciding between the Ryzen 7900X3D and 7800X3D. The price difference in my country is miniscule, so what’s keeping me up at night is the 2 CCD situation on the 7900X3D.

I’m purely running Linux and use my PC both for work (involves compilation, containerization, VMs) as well as gaming mainly through Steam/Proton.

So my question is: Does anyone know if the process scheduler in Linux works better than the Windows one for these heteregenous CPUs?
E.g. will it pick the v-cache enabled threads for gaming out-of-the-box or not?

As far as I can tell from early reviews on Phoronix it didn’t work well back then, but I haven’t been able to find updated information.

One suggestion I did stumble upon was reducing core frequency on the non-v-cache cores in UEFI. I can live with a slightly lower boost clock on the second CCD, but I can’t find any information about the process scheduler using boost frequency for its decision making either.
Finally I’m normally using the amd-pstate driver with the schedutil governor.

I hope someone here has some insights into the matter, to ease my buying decision :slight_smile:

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There’s a lazier approach that doesn’t involve testing or really even knowing anything - if there’s really a miniscule difference in cost for you, go with the 7900X3D - and disable the second CCD’s cores if it’s some kind of percievable problem. Try again every major kernel release; improvements are constant - https://www.phoronix.com/news/AMD-P-State-Preferred-Core-69 but you can’t download extra cores later (don’t suggest it to intel).

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