Re: [RFC/RFT][PATCH 0/4] cpufreq / sched: iowait boost in intel_pstate and schedutil

From: Srinivas Pandruvada
Date: Thu Sep 08 2016 - 13:31:07 EST


On Thu, 2016-09-08 at 17:02 +0200, Rafael J. Wysocki wrote:
> On Thursday, September 08, 2016 03:15:49 AM Rafael J. Wysocki wrote:
> >
> > On Wednesday, September 07, 2016 05:49:31 PM Srinivas Pandruvada
> > wrote:
> > >
> > > On Thu, 2016-09-08 at 02:44 +0200, Rafael J. Wysocki wrote:
> > > >
> > > > On Wednesday, September 07, 2016 05:35:50 PM Srinivas
> > > > Pandruvada
> > > > wrote:
> > > > >
> > > > >
> > > > > On Wed, 2016-09-07 at 17:22 -0700, Steve Muckle wrote:
> > > > > >
> > > > > >
> > > > > > On Sat, Sep 03, 2016 at 02:56:48AM +0200, Rafael J. Wysocki
> > > > > > wrote:
> > > > > > >
> > > > > > >
> > > > > > >
> > > > > > > Please let me know what you think and if you can run some
> > > > > > > benchmarks you
> > > > > > > care about and see if the changes make any difference
> > > > > > > (this way
> > > > > > > or
> > > > > > > another),
> > > > > > > please do that and let me know what you've found.
> > > > > >
> > > > > > LGTM (I just reviewed the first and last patch, skipping
> > > > > > the
> > > > > > intel_pstate ones).
> > > > > >
> > > > > > I was unable to see a conclusive power regression in
> > > > > > Android
> > > > > > audio,
> > > > > > video or
> > > > > > idle usecases on my hikey 96board.
> > > > > Did you see any performance regression on Android workloads?
> > > >
> > > > That's with schedutil and IOwait boost.ÂÂWhy would performance
> > > > regress?
> > > Some Android tests reach thermal limits and aggressive throttling
> > > causes performance issues.Â
> >
> > I see, OK.
>
> But in that case Steve would see a power regression as well IMO.
> ÂÂIt would
> be rather difficult to reach thermal limits without consuming more
> energy,
> wouldn't it? :-)
Yes. It depends on workloads. Idle and AV tests which tend to use HW
encoding/decoding don't stress CPU enough in my experience. May be
something like CPU Mark or Disk mark score.

Anyway this shouldn't be a reason for not including a change.

Thanks,
Srinivas

>
> Thanks,
> Rafael
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-pm"
> in
> the body of a message to majordomo@xxxxxxxxxxxxxxx
> More majordomo info atÂÂhttp://vger.kernel.org/majordomo-info.html