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Subject: Re: [PATCH] sched, fair: Allow a small load imbalance between low
 utilisation SD_NUMA domains v4
To:     Mel Gorman <mgorman@techsingularity.net>,
        Vincent Guittot <vincent.guittot@linaro.org>
Cc:     Phil Auld <pauld@redhat.com>, Ingo Molnar <mingo@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Srikar Dronamraju <srikar@linux.vnet.ibm.com>,
        Quentin Perret <quentin.perret@arm.com>,
        Dietmar Eggemann <dietmar.eggemann@arm.com>,
        Morten Rasmussen <Morten.Rasmussen@arm.com>,
        Hillf Danton <hdanton@sina.com>,
        Parth Shah <parth@linux.ibm.com>,
        Rik van Riel <riel@surriel.com>,
        LKML <linux-kernel@vger.kernel.org>
References: <20200114101319.GO3466@techsingularity.net>
 <20200116163529.GP3466@techsingularity.net>
From:   Valentin Schneider <valentin.schneider@arm.com>
Message-ID: <4cd0dda0-a944-b0ac-a614-6127b60babe6@arm.com>
Date:   Fri, 17 Jan 2020 14:37:28 +0000
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On 16/01/2020 16:35, Mel Gorman wrote:
> Any thoughts on whether this is ok for tip or are there suggestions on
> an alternative approach?
> 

My main concern was about using number of tasks instead of number of busy
CPUs, which you're doing here, so I'm happy with that side of things.

As for the simpler imbalance heuristic, I don't have any issue with it
either. It's obvious that it caters to pairs of communicating tasks, and
we can try to extend it later on if required.

So yeah, FWIW:
Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>