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

From: Rafael J. Wysocki
Date: Thu Sep 08 2016 - 10:56:13 EST


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. Why would performance
> > > regress?
> > Some Android tests reach thermal limits and aggressive throttling
> > causes performance issues.
>
> I see, OK.

But in that case Steve would see a power regression as well IMO. It would
be rather difficult to reach thermal limits without consuming more energy,
wouldn't it? :-)

Thanks,
Rafael