Re: stable 6.6: commit "sched/cpufreq: Rework schedutil governor performance estimation' causes a regression
From: Christian Loehle
Date: Thu Nov 20 2025 - 05:15:16 EST
On 11/20/25 04:45, Sergey Senozhatsky wrote:
> Hi,
>
> We are observing a performance regression on one of our arm64 boards.
> We tracked it down to the linux-6.6.y commit ada8d7fa0ad4 ("sched/cpufreq:
> Rework schedutil governor performance estimation").
>
> UI speedometer benchmark:
> w/commit: 395 +/-38
> w/o commit: 439 +/-14
>
Hi Sergey,
Would be nice to get some details. What board? What do the OPPs look like?
Does this system use uclamp during the benchmark? How?
Given how large the stddev given by speedometer (version 3?) itself is, can we get the
stats of a few runs?
Maybe traces of cpu_frequency for both w/ and w/o?