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Date: Wed, 16 Sep 2015 17:36:55 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: bsegall@google.com
Cc: Morten Rasmussen <morten.rasmussen@arm.com>,
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Subject: Re: [PATCH 5/6] sched/fair: Get rid of scaling utilization by
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On Mon, Sep 14, 2015 at 10:34:00AM -0700, bsegall@google.com wrote:

> It has never been clear to me what
> SCHED_LOAD_SCALE/SCHED_LOAD_SHIFT were for as opposed to NICE_0_LOAD,

SCHED_LOAD_SCALE/SHIFT are the fixed point mult/shift, and NICE_0_LOAD
is the load of a nice-0 task. They happen to be the same by the choice
that nice-0 has a load of 1 (the only natural choice given proportional
weight and hyperboles etc..).

But for the fixed point math we use SCHED_LOAD_* and only when we want
to explicitly use the unit load we use NICE_0_LOAD (its only used 4-5
times or so).