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From: Mel Gorman <mgorman@techsingularity.net>
Newsgroups: linux.kernel
Subject: Re: [PATCH 1/2] sched/wait: Break up long wake list walk
Date: Thu, 24 Aug 2017 22:50:02 +0200
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X-Original-Cc: Tim Chen <tim.c.chen@linux.intel.com>, "Liang, Kan" <kan.liang@intel.com>, Mel Gorman <mgorman@suse.de>, "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>, Peter Zijlstra <peterz@infradead.org>, Ingo Molnar <mingo@elte.hu>, Andi Kleen <ak@linux.intel.com>, Andrew Morton <akpm@linux-foundation.org>, Johannes Weiner <hannes@cmpxchg.org>, Jan Kara <jack@suse.cz>, linux-mm <linux-mm@kvack.org>, Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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On Thu, Aug 24, 2017 at 11:16:15AM -0700, Linus Torvalds wrote:
> On Thu, Aug 24, 2017 at 10:49 AM, Tim Chen <tim.c.chen@linux.intel.com> wrote:
> >
> > These changes look fine.  We are testing them now.
> > Does the second patch in the series look okay to you?
> 
> I didn't really have any reaction to that one, as long as Mel&co are
> ok with it, I'm fine with it.
> 

I've no strong objections or concerns. I'm disappointed that the
original root cause for this could not be found but hope that eventually a
reproducible test case will eventually be available. Despite having access
to a 4-socket box, I was still unable to create a workload that caused
large delays on wakeup. I'm going to have to stop as I don't think it's
possible to create on that particular machine for whatever reason.

-- 
Mel Gorman
SUSE Labs