RE: [PATCH v2 0/3] cpufreq: Allow drivers to receive more information from the governor

Doug Smythies
2020-12-17T15:27:37Z

On 2020.12.14 12:02 Rafael J. Wysocki wrote:

> Hi,

Hi Rafael,

V2 test results below are new, other results are partially re-stated:

For readers that do not want to read on, I didn't find anything different than with
the other versions. This was more just due diligence.

Legend:

hwp: Kernel 5.10-rc6, HWP enabled; intel_cpufreq
rfc (or rjw): Kernel 5.10-rc6 + this patch set, HWP enabled; intel_cpu-freq; schedutil
no-hwp: Kernel 5.10-rc6, HWP disabled; intel_cpu-freq
acpi (or acpi-cpufreq): Kernel 5.10-rc6, HWP disabled; acpi-cpufreq; schedutil
patch: Kernel 5.10-rc7 + V1 patch set, HWP enabled; intel_cpu-freq; schedutil
v2: Kernel 5.10-rc7 + V2 patch set, HWP enabled; intel_cpu-freq; schedutil

Fixed work packet, fixed period, periodic workflow, load sweep up/down:

load work/sleep frequency: 73 Hertz:

hwp: Average: 12.00822 watts
rjw: Average: 10.18089 watts
no-hwp: Average: 10.21947 watts
acpi-cpufreq: Average: 9.06585 watts
patch: Average: 10.26060 watts
v2: Average: 10.50444

load work/sleep frequency: 113 Hertz:

hwp: Average: 12.01056
rjw: Average: 10.12303
no-hwp: Average: 10.08228
acpi-cpufreq: Average: 9.02215
patch: Average: 10.27055
v2: Average: 10.31097

load work/sleep frequency: 211 Hertz:

hwp: Average: 12.16067
rjw: Average: 10.24413
no-hwp: Average: 10.12463
acpi-cpufreq: Average: 9.19175
patch: Average: 10.33000
v2: Average: 10.39811

load work/sleep frequency: 347 Hertz:

hwp: Average: 12.34169
rjw: Average: 10.79980
no-hwp: Average: 10.57296
acpi-cpufreq: Average: 9.84709
patch: Average: 10.67029
v2: Average: 10.93143

load work/sleep frequency: 401 Hertz:

hwp: Average: 12.42562
rjw: Average: 11.12465
no-hwp: Average: 11.24203
acpi-cpufreq: Average: 10.78670
patch: Average: 10.94514
v2: Average: 11.50324

Serialized single threaded via PIDs per second method:
A.K.A fixed work packet, variable period
Results:

Execution times (seconds. Less is better):

no-hwp:

performance: Samples: 382 ; Average: 10.54450 ; Stand Deviation: 0.01564 ; Maximum: 10.61000 ; Minimum: 10.50000

schedutil: Samples: 293 ; Average: 13.73416 ; Stand Deviation: 0.73395 ; Maximum: 15.46000 ; Minimum: 11.68000
acpi: Samples: 253 ; Average: 15.94889 ; Stand Deviation: 1.28219 ; Maximum: 18.66000 ; Minimum: 12.04000

hwp:

schedutil: Samples: 380 ; Average: 10.58287 ; Stand Deviation: 0.01864 ; Maximum: 10.64000 ; Minimum: 10.54000
patch: Samples: 276 ; Average: 14.57029 ; Stand Deviation: 0.89771 ; Maximum: 16.04000 ; Minimum: 11.68000
rfc: Samples: 271 ; Average: 14.86037 ; Stand Deviation: 0.84164 ; Maximum: 16.04000 ; Minimum: 12.21000
v2: Samples: 274 ; Average: 14.67978 ; Stand Deviation: 1.03378 ; Maximum: 16.07000 ; Minimum: 11.43000

Power (watts. More indicates higher CPU frequency and better performance. Sample time = 1 second.):

no-hwp:

performance: Samples: 4000 ; Average: 25.41355 ; Stand Deviation: 0.22156 ; Maximum: 26.01996 ; Minimum: 24.08807

schedutil: Samples: 4000 ; Average: 12.58863 ; Stand Deviation: 5.48600 ; Maximum: 25.50934 ; Minimum: 7.54559
acpi: Samples: 4000 ; Average: 9.57924 ; Stand Deviation: 5.41157 ; Maximum: 25.06366 ; Minimum: 5.51129

hwp:

schedutil: Samples: 4000 ; Average: 25.24245 ; Stand Deviation: 0.19539 ; Maximum: 25.93671 ; Minimum: 24.14746
patch: Samples: 4000 ; Average: 11.07225 ; Stand Deviation: 5.63142 ; Maximum: 24.99493 ; Minimum: 3.67548
rfc: Samples: 4000 ; Average: 10.35842 ; Stand Deviation: 4.77915 ; Maximum: 24.95953 ; Minimum: 7.26202
v2: Samples: 4000 ; Average: 10.98284 ; Stand Deviation: 5.48859 ; Maximum: 25.76331 ; Minimum: 7.53790