On 04/02/21 13:03, Dietmar Eggemann wrote: > How did you verify the benefit of these changes? > > It's clear that you need a platform with capacity_orig diffs <20% > between CPU types (like Pixel4 - SD855 (4x261, 3x871, 1x1024) or QC's > RB5 platform - SD865 (4x284, 3x871, 1*1024)) but which > benchmark/testcase did you use?
Benchmark is the usual culprit: https://lisa-linux-integrated-system-analysis.readthedocs.io/en/master/kernel_tests.html#lisa.tests.scheduler.misfit.StaggeredFinishes This test spawns 1 CPU hog per CPU, and screams whenever a CPU of capacity X is running a hog while another CPU of capacity Y > X has been idling for "too long" (a few ms). IOW it makes sure upmigration happens in a timely manner. Some of the test platforms (Juno (4+2 big.LITTLE), HiKey960 (4+4 big.LITTLE)) show some improvements due to the last 2 patches. As for systems with CPUs in the [819-1024] "deadzone", Ionela's been kindly running said test on said RB5, and the upmigrations look just fine with the patches applied.
