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Date: Tue, 10 Jan 2012 09:44:52 +0000
From: Mel Gorman <mgorman@suse.de>
To: Hillf Danton <dhillf@gmail.com>
Cc: linux-mm@kvack.org, KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>,
        David Rientjes <rientjes@google.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] mm: vmscan: fix setting reclaim mode
Message-ID: <20120110094452.GC4118@suse.de>
References: <CAJd=RBAqzawZ=jEFt7TrZgU0gaejMkfiBxzH7Y19qqNnsZrJGw@mail.gmail.com>
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On Sun, Jan 08, 2012 at 03:05:03PM +0800, Hillf Danton wrote:
> The check for under memory pressure is corrected, then lumpy reclaim or
> reclaim/compaction could be avoided either when for order-O reclaim or
> when free pages are already low enough.
> 

No explanation of problem, how this patch fixes it or what the impact
is.

At a glance, this will have the impact of using sync reclaim at low
reclaim priorities. This is unexpected so needs much better explanation.

-- 
Mel Gorman
SUSE Labs