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Date:   Tue, 5 Jun 2018 15:09:54 +0100
From:   Quentin Perret <quentin.perret@arm.com>
To:     Vincent Guittot <vincent.guittot@linaro.org>
Cc:     Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@kernel.org>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        "Rafael J. Wysocki" <rjw@rjwysocki.net>,
        Juri Lelli <juri.lelli@redhat.com>,
        Dietmar Eggemann <dietmar.eggemann@arm.com>,
        Morten Rasmussen <Morten.Rasmussen@arm.com>,
        viresh kumar <viresh.kumar@linaro.org>,
        Valentin Schneider <valentin.schneider@arm.com>
Subject: Re: [PATCH v5 00/10] track CPU utilization
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On Tuesday 05 Jun 2018 at 15:55:43 (+0200), Vincent Guittot wrote:
> On 5 June 2018 at 15:52, Quentin Perret <quentin.perret@arm.com> wrote:
> > On Tuesday 05 Jun 2018 at 15:18:38 (+0200), Vincent Guittot wrote:
> >> On 5 June 2018 at 15:12, Quentin Perret <quentin.perret@arm.com> wrote:
> >> I would say no because when one will decrease the other one will not
> >> increase at the same pace and we will have some wrong behavior or
> >> decision
> >
> > I think I get your point. Yes, sometimes, the slow-moving rt_avg can be
> > off a little bit (which can be good or bad, depending in the case) if your
> > RT task runs a lot with very changing behaviour. And again, I'm not
> > fundamentally against the idea of having extra complexity for RT/IRQ PELT
> > signals _if_ we have a use-case. But is there a real use-case where we
> > really need all of that ? That's a true question, I honestly don't have
> > the answer :-)
> 
> The iperf test result is another example of the benefit

The iperf test result ? The sysbench test you mean ?