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Date: Thu, 3 Mar 2016 17:47:51 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Vincent Guittot <vincent.guittot@linaro.org>,
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Subject: Re: [PATCH 6/6] cpufreq: schedutil: New governor based on scheduler
 utilization data
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On Thu, Mar 03, 2016 at 05:37:35PM +0100, Peter Zijlstra wrote:
> On Thu, Mar 03, 2016 at 05:24:32PM +0100, Rafael J. Wysocki wrote:
> > >> f = a * x + b

> > If not, then I think it's reasonable to map the middle of the
> > available frequency range to x = 0.5 and then we have b = 0 and a =
> > (max_freq + min_freq) / 2.
> 
> So I really think that approach falls apart on the low util bits, you
> effectively always run above min speed, even if min is already vstly
> over provisioned.

Ah nevermind, I cannot read. Yes that is worth trying I suppose. But the
b=0,a=1 thing seems more natural still.