Re: [RFC/RFT][PATCH] cpufreq: intel_pstate: Accept passive mode with HWP enabled

On Sun, 2020-05-31 at 11:59 -0700, Srinivas Pandruvada wrote:

On Sun, 2020-05-31 at 11:06 -0700, Doug Smythies wrote:

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Hi Srinivas,

Thanks you for your quick reply.

On 2020.05.31 09:54 Srinivas Pandruvada wrote

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On Sun, 2020-05-31 at 09:39 -0700, Doug Smythies wrote:

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Event begins at 17.456 seconds elapsed time.
Previous event was about 107 milliseconds ago.

Old min ; new min ; freq GHz; load % ; duration mS
27      ; 28      ; 4.60    ; 68.17  ; 10.226
28      ; 26      ; 4.53    ; 57.47  ; 10.005

Seems you hit power/thermal limit

No.

I am nowhere near any power limit at all.
I have meticulously configured and tested the thermal management of
this computer.
I never ever hit a thermal limit and have TDP set such that the
processor
temperature never exceeds about 75 degrees centigrade.

There should never be throttling involved in these experiments.
I can achieve throttling when compiling the kernel and with
torture test mode on the mprime test (other CPU stressors,
including my own, are not as good at generating heat as
mprime).

This system can run indefinitely at 99.9 watts processor package
power.
Example (turbostat, steady state, CPU freq throttled to 4.04 GHz):

doug@s18:~$ sudo ~/turbostat --Summary --quiet --show
Busy%,Bzy_MHz,PkgTmp,PkgWatt,GFXWatt,IRQ --interval 12
Busy%   Bzy_MHz IRQ     PkgTmp  PkgWatt GFXWatt
100.21  4045    72231   66      99.93   0.00
100.21  4043    72239   65      99.92   0.00

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Is this some Lenovo system?

No. The web page version of my original e-mail has
a link to the test computer hardware profile.

The motherboard is ASUS PRIME Z390-P.

OK, this seems a desktop system.

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If you disable HWP you don't see that?

Correct.

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What is the value of
cat /sys/bus/pci/devices/0000\:00\:04.0/tcc_offset_degree_celsius

? "No such file or directory"

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cat /sys/class/powercap/intel-rapl-mmio/intel-rapl-
mmio:0/constraint_0_power_limit_uw

You may not have
CONFIG_INT340X_THERMAL=y

What is
#rdmsr 0x1a2

Try changing energy_perf_bias and see if it helps here.

Also if
MSR 0x1FC bit 19 is 0, change to 1.

Thanks,
Srinivas

Thanks,
Srinivas

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? "No such file or directory"
 

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You may want to run
Try running dptfxtract once.

No, I am not going to.

I am not running thermald. Eventually I will, as a backup
in case of cooling failure, so as not to hit the processor limit
shutdown. I just haven't done it yet.

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Then try to get again

cat /sys/bus/pci/devices/0000\:00\:04.0/tcc_offset_degree_celsius
cat /sys/class/powercap/intel-rapl-mmio/intel-rapl-
mmio:0/constraint_0_power_limit_uw


Thanks,
Srinivas