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by thrownaway2424 4696 days ago
No, the power-aware scheduler in Linux does not work as you describe. On a turbo-capable Intel CPU, if there are N program threads that will fit on M cores where M is less than the total cores on a socket, and the CPU will enter P0 state, then the threads will run on as few cores as possible and the remaining cores will be shut down.
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Two threads, each running at 100%, will be assigned to two physical cores. This is reality, and is obvious given that assigning it to a physical core and a hyperthread core at most will give you about 130% instead of the 200% two physical cores will provide.

Unless, of course, you've set a power profile to prioritize power efficiency, but that would be an absolutely ridiculous assumption given that we're talking about benchmarks.