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Date: Tue, 8 Sep 2015 17:33:00 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Morten Rasmussen <morten.rasmussen@arm.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>,
        Dietmar Eggemann <dietmar.eggemann@arm.com>,
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Subject: Re: [PATCH 5/6] sched/fair: Get rid of scaling utilization by
 capacity_orig
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On Tue, Sep 08, 2015 at 03:31:58PM +0100, Morten Rasmussen wrote:
> On Tue, Sep 08, 2015 at 02:52:05PM +0200, Peter Zijlstra wrote:
> > > Tricky that, LOAD_AVG_MAX very much relies on the unit being 1<<10.
> 
> I don't get why LOAD_AVG_MAX relies on the util_avg shifting being
> 1<<10, it is just the sum of the geometric series and the upper bound of
> util_sum?

It needs a 1024, it might just have been the 1024 ns we use a period
instead of the scale unit though.

The LOAD_AVG_MAX is the number where adding a next element to the series
doesn't change the result anymore, so scaling it up will allow more
significant elements to the series before we bottom out, which is the _N
thing.