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Date: Wed, 8 Jul 2015 15:56:45 +0200
From: Ingo Molnar <mingo@kernel.org>
To: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>, linux-kernel@vger.kernel.org,
        Rik van Riel <riel@redhat.com>, Mel Gorman <mgorman@suse.de>
Subject: Re: [PATCH] sched/numa: Restore sched feature NUMA to its earlier
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* Srikar Dronamraju <srikar@linux.vnet.ibm.com> wrote:

> In commit:8a9e62a "sched/numa: Prefer NUMA hotness over cache hotness"
> sched feature NUMA was always set to true. However this sched feature was
> suppose to be enabled on NUMA boxes only thro set_numabalancing_state().
>
> To get back to the above behaviour, bring back NUMA_FAVOUR_HIGHER feature.

Three typos and a non-standard commit ID reference.

>  /*
> + * NUMA_FAVOUR_HIGHER will favor moving tasks towards nodes where a
> + * higher number of hinting faults are recorded during active load
> + * balancing. It will resist moving tasks towards nodes where a lower
> + * number of hinting faults have been recorded.
>   */
> -SCHED_FEAT(NUMA,	true)
> +SCHED_FEAT(NUMA_FAVOUR_HIGHER, true)
>  #endif
> 

So the comment spells 'favor' American, the constant you introduce is British 
spelling via 'FAVOUR'? Please use it consistently!

Also, this name is totally non-intuitive.

Make it something like NUMA_FAVOR_BUSY_NODES or so?

Also, I'm wondering how this can schedule in a stable fashion: if a non-busy node 
is not favored, how can we end up there to start building up hinting faults?

Thanks,

	Ingo