AMD Schedutil vs. Performance Governor Benchmarks On Linux 5.11 Shows More Upside Potential

[Snaipersky]

When will they just give this up already? It's been years and years, and still sucks, and beyond still being bad, it's trying to replace options that are actually good. Performance, powersave, even ondemand. Schedutil is just overcomplicated and underperforming.

[MadCatX]

Schedutil was about as fast as ondemand in the last PHX benchmarks I've seen. The performance varied based on the specific tests but overall I think that schedutil even came out slightly ahead. With the recent improvements it'd probably outperform ondemand. If they manage to fix the utilization calculation properly for 5.12 I'd be an interesting benchmark.

[darkbasic]

Why can't Linux enter the 21th century and implement continuous integration like everyone else? Obviously you can't test everything but some regressions are simply too obvious to be ignored.

[brent]

My gut feeling is better idle efficiency

No, idle power usage is the same. P-state scheduling doesn't affect C-states. Efficiency might be a bit better with some "spiky" loads with many wakeups, but still lots of idle time, though.

Overall... I'm still not impressed by schedutil, not at all. A CPPC2 based scheduler has some intrinsic advantages and should result in some actually tangible differences. Hope we'll see it some day.

[milkylainen]

As I suspected. Not impressed.
Idle power not changed, working power not optimized (beside actual loss of performance),
too many corner cases and just adding code.
Nope.
Will still run performance thank you.

[Vistaus]

How can I enable schedutil on Intel? It doesn't appear in the available governors list (using both kernel 5.4 and 5.10).

[ciupenhauer]

How can I enable schedutil on Intel? It doesn't appear in the available governors list (using both kernel 5.4 and 5.10).

intel_pstate=passive in the kernel boot parameter list

[Vistaus]

intel_pstate=passive in the kernel boot parameter list

Thanks, I tried that, but schedutil still doesn't appear in the list of available governors.

[andreano]

schedutil still doesn't appear in the list of available governors

Check if it is enabled in your kernel:

[FONT=monospace][COLOR=#005fd7]zcat[/COLOR][COLOR=#00afff] /proc/config.gz[/COLOR][COLOR=#18b218] | [/COLOR][COLOR=#005fd7]grep [/COLOR][COLOR=#00afff]SCHEDUTIL[/COLOR]
CONFIG_CPU_FREQ_DEFAULT_GOV_[COLOR=#ff5454][B]SCHEDUTIL[/B][/COLOR][COLOR=#000000]=y [/COLOR]
CONFIG_CPU_FREQ_GOV_[COLOR=#ff5454][B]SCHEDUTIL[/B][/COLOR][COLOR=#000000]=y[/COLOR][/FONT]

[andreano]

I want a CPU governor that ignores "nice" load.

Edit: Some searching later:

[FONT=monospace][COLOR=#005fd7]echo [/COLOR][COLOR=#00afff]1 [/COLOR][COLOR=#18b218]| [/COLOR][COLOR=#005fd7]sudo [/COLOR][COLOR=#00afff]tee[/COLOR][COLOR=#00afff]/sys/devices/system/cpu/cpufreq/ondemand/ignore_nice_load[/COLOR][/FONT]