On Mon, 27 Jan 2020 at 22:55, <lukasz.luba@xxxxxxx> wrote: > > From: Lukasz Luba <lukasz.luba@xxxxxxx> > > Enable the Energy Model (EM) brings possibility to use Energy Aware > Scheduler (EAS). This compiles the EM but does not enable to run EAS in > default. The EAS only works with SchedUtil - a CPUFreq governor which > handles direct requests from the scheduler for the frequency change. Thus, > to make EAS working in default, the SchedUtil governor should be > configured as default CPUFreq governor. Full stop. That's enough of needed explanation of schedutil. > Although, the EAS might be enabled > in runtime, when the EM is present for CPUs, the SchedUtil is compiled and > then set as CPUFreq governor, i.e.: > > echo schedutil > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor > echo schedutil > /sys/devices/system/cpu/cpu4/cpufreq/scaling_governor > > To check if EAS is ready to work, the read output from the command below > should show '1': > cat /proc/sys/kernel/sched_energy_aware > > To disable EAS in runtime simply 'echo 0' to the file above. Not related to this commit. If you were implemeting here schedutil/EAS, then it makes sense to post all this. However what's the point to describe it in every defconfig change? > Some test results, which stress the scheduler on Odroid-XU3: > hackbench -l 500 -s 4096 > With mainline code and with this patch set. Skip the last sentence - duplicated information. > > The tests have been made with and without CONFIG_PROVE_LOCKING (PL) > (which is set to =y in default exynos_defconfig) > > | this patch set | mainline The commit will be applied on its own branch so the meaning of "this patch set" will be lost. Maybe just "before/after"? > |-----------------------------------------------|--------------- > | performance | SchedUtil | SchedUtil | performance > | governor | governor | governor | governor > | | w/o EAS | w/ EAS | > ----------------|---------------|---------------|---------------|--------------- > hackbench w/ PL | 12.7s | 11.7s | 12.0s | 13.0s - 12.2s > hackbench w/o PL| 9.2s | 8.1s | 8.2s | 9.2s - 8.4s Why does the performance different before and after this patch? Mention - lower better (?). Space between number and unit... or better mention [s] in column title. And last but not least: Why this patch is separate from 1/3? I don't get the need of splitting them. Best regards, Krzysztof
