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Date: Wed, 24 Jul 2013 09:48:42 -0700
From: Arjan van de Ven <arjan@linux.intel.com>
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To: Morten Rasmussen <morten.rasmussen@arm.com>
CC: Catalin Marinas <Catalin.Marinas@arm.com>,
        Peter Zijlstra <peterz@infradead.org>,
        "mingo@kernel.org" <mingo@kernel.org>,
        "vincent.guittot@linaro.org" <vincent.guittot@linaro.org>,
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        "efault@gmx.de" <efault@gmx.de>, "pjt@google.com" <pjt@google.com>,
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Subject: Re: [RFC][PATCH 0/9] sched: Power scheduler design proposal
References: <1373385338-12983-1-git-send-email-morten.rasmussen@arm.com> <20130713064909.GW25631@dyad.programming.kicks-ass.net> <20130713102350.GA8067@MacBook-Pro.local> <20130715203922.GD23818@dyad.programming.kicks-ass.net> <20130716124248.GB10036@arm.com> <51E5655C.7050304@linux.intel.com> <20130717141426.GG27948@arm.com> <20130724135011.GE12572@e103034-lin> <51EFEFD4.4020808@linux.intel.com> <20130724164607.GF12572@e103034-lin>
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>
> I would expect performance to be disjoint for most tasks. If there was
> an overlap, the big would probably be less power efficient (as in
> energy/instruction) than the little so you would prefer to run on the
> little anyway.
>
> In what way would you use the overlap?

if the scheduler thinks a task would be better off on the other side
than where it is now, it could first move it into the "overlap area" on the
same side by means of experiment, and if the task behaves as expected there,
THEN move it over.