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At the end, at > > least in my case, it seems all compliant with the ACPI/CPPC specs and > > suggesting to equalize them because "the kernel doesn't handle it well" > > doesn't seem like a solid motivation... > > The first time we observed this on NVIDIA Grace, we wondered whether > there might be functionality outside the task scheduler that makes use > of these slightly heterogeneous CPU capacity values from CPPC—and > whether the dependency on task scheduling was simply an overlooked > phenomenon. > > And then there was DCPerf Mediawiki on 72 CPUs system always scoring > better with sched_asym_cpucap_active() = TRUE (mentioned already by > Chris L. in: > https://lore.kernel.org/r/15ffdeb3-a0f3-4b88-92c0-17ffb03b0574@arm.com Yeah, I think Chris' asym-packing approach might be the safest thing to do. At the same time it would be nice to improve asym-capacity to introduce some concept of SMT awareness, that was my original attempt with https://lore.kernel.org/all/20260318092214.130908-1-arighi@nvidia.com, since we may see similar asym-capacity benefits on Vera (that has SMT, unlike Grace). What do you think? Thanks, -Andrea