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From: Peter Zijlstra <peterz@infradead.org>
To: Mel Gorman <mgorman@techsingularity.net>
Cc: Mike Galbraith <efault@gmx.de>,
	Matt Fleming <matt@codeblueprint.co.uk>,
	LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 1/2] sched/fair: Consider SD_NUMA when selecting the most idle group to schedule on
Date: Tue, 13 Feb 2018 14:04:45 +0100	[thread overview]
Message-ID: <20180213130445.GH25201@hirez.programming.kicks-ass.net> (raw)
In-Reply-To: <20180213113548.tb7zxzly32oz3mfb@techsingularity.net>

On Tue, Feb 13, 2018 at 11:35:48AM +0000, Mel Gorman wrote:
> > However, if we have numa balancing enabled, that will counteract
> > the normal spreading across nodes, so in that regard it makes sense, but
> > the above code is not conditional on numa balancing.
> > 
> 
> It's not conditional on NUMA balancing because one case where it mattered
> was a fork-intensive workload driven by shell scripts. In that case, the
> workload benefits from preferring a local node without any involvement from
> NUMA balancing. I could make it conditional on it but it's not strictly
> related to automatic NUMA balancing, it's about being less eager about
> starting new children on remote nodes.

Yeah, I suppose. And you're right, there's no real winning this. It's
all tea-leaves and entrails.

In any case, I think I prefer the kill sync early variant and you were
going to ammend some comments. Can you respin and resend all these
patches (can do in a single series)?

  reply	other threads:[~2018-02-13 13:04 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-02-12 17:11 [PATCH 0/2] Stop wake_affine fighting with automatic NUMA balancing Mel Gorman
2018-02-12 17:11 ` [PATCH 1/2] sched/fair: Consider SD_NUMA when selecting the most idle group to schedule on Mel Gorman
2018-02-13 10:45   ` Peter Zijlstra
2018-02-13 11:35     ` Mel Gorman
2018-02-13 13:04       ` Peter Zijlstra [this message]
2018-02-13 13:29         ` Mel Gorman
2018-02-12 17:11 ` [PATCH 2/2] sched/numa: Delay retrying placement for automatic NUMA balance after wake_affine Mel Gorman
2018-02-12 17:34   ` Peter Zijlstra
2018-02-12 17:52     ` Mel Gorman
2018-02-12 17:37   ` Peter Zijlstra
2018-02-12 18:11     ` Mel Gorman

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