Re: [PATCH] tools/power turbostat: Fix Bzy_MHz calculation equation

From: Wyes Karny
Date: Fri Nov 03 2023 - 00:48:58 EST


On 02 Nov 08:31, Doug Smythies wrote:
> Hi Peng and Wyes,
>
> Just for your information about your recent "ping"s about your turbostat patches:
>
> Please be aware that there is rarely any reply. There tends to be about 2 turbostat updates released per year. Your patches are in patchworks [1], as are some others, including an old one of mine from 2023.04.03
> Eventually there will be an update, and hopefully it will include all our patches.

Thanks Doug for the information.

Regards,
Wyes
>
> [1] https://patchwork.kernel.org/project/linux-pm/list/?series=&submitter=&state=&q=&archive=&delegate=107
>
> ... Doug
>
> On 2023.10.29 08:12 Peng Liu wrote:
>
> > Ping
> >
> > On 2023/10/7 13:46, Peng Liu wrote:
> >> From: Peng Liu <liupeng17@xxxxxxxxxx>
> >>
> >> To calculate Bzy_MHz, TSC_delta should multiply APERF_delta instead
> >> of dividing it.
> >>
> >> Signed-off-by: Peng Liu <liupeng17@xxxxxxxxxx>
> >> ---
> >> tools/power/x86/turbostat/turbostat.8 | 2 +-
> >> 1 file changed, 1 insertion(+), 1 deletion(-)
> >>
> >> diff --git a/tools/power/x86/turbostat/turbostat.8 b/tools/power/x86/turbostat/turbostat.8
> >> index 8f08c3fd498d..1ba6340d3b3d 100644
> >> --- a/tools/power/x86/turbostat/turbostat.8
> >> +++ b/tools/power/x86/turbostat/turbostat.8
> >> @@ -370,7 +370,7 @@ below the processor's base frequency.
> >>
> >> Busy% = MPERF_delta/TSC_delta
> >>
> >> -Bzy_MHz = TSC_delta/APERF_delta/MPERF_delta/measurement_interval
> >> +Bzy_MHz = TSC_delta*APERF_delta/MPERF_delta/measurement_interval
> >>
> >> Note that these calculations depend on TSC_delta, so they
> >> are not reliable during intervals when TSC_MHz is not running at the base frequency.
>