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Message-ID: <1466048008.2780.5.camel@gmail.com>
Subject: Re: [rfc patch] sched/fair: Use instantaneous load for fork/exec
 balancing
From: Mike Galbraith <umgwanakikbuti@gmail.com>
To: Dietmar Eggemann <dietmar.eggemann@arm.com>,
        Peter Zijlstra <peterz@infradead.org>
Cc: Yuyang Du <yuyang.du@intel.com>, LKML <linux-kernel@vger.kernel.org>
Date: Thu, 16 Jun 2016 05:33:28 +0200
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On Wed, 2016-06-15 at 20:03 +0100, Dietmar Eggemann wrote:

> Isn't there a theoretical problem with the scale_load() on CONFIG_64BIT
> machines on tip/sched/core? load.weight has a higher resolution than
> runnable_load_avg (and so the values in the rq->cpu_load[] array).
> Theoretically because [forkexec|wake]_idx is 0 so [target|source]_load()
> is nothing else than weighted_cpuload().

I see a not so theoretical problem with my rfc in that I forgot to
scale_load_down() if that's what you mean.

(changes nothing, reality was just extra special unadulterated;)

	-Mike