Comment 11 for bug 1885730

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Colin Ian King (colin-king) wrote : Re: Bring back ondemand.service or switch kernel default governor for pstate - pstate now defaults to performance governor

The choice was made from running analysis on a wide range of Intel machines, old and new. We are trying to select the optimal choice for a wide range of CPUs for a wide range of use cases. Generally speaking, the intel-pstate governor has deeper understanding of the processor features and can access CPU metrics that can guide it to making an informed choice.

From our understanding, The intel-pstate driver should be the optimal choice for Intel Sandy Bridge CPUs onwards. The intel-pstate driver supports only the performance and powersave governors. In benchmarking we didn't observe much computational difference between the too once the CPU is fully loaded. However, cranking up or cranking down the load one will discover that the performance setting is more responsive than powersave. The overall compute throughput when fully loaded is the same, it's just a case that powersave may take a little longer to crank up to the full speed.

It makes sense to default to powersave for most scenarios, especially for laptop users.

Pre-Intel Sandy Bridge or non-x86 CPUs will default back to the non-intel pstate governor.

So, question:

Which kernel(s) are you referring to?