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Date: Fri, 10 Dec 2010 00:59:25 +0900
From: Minchan Kim <minchan.kim@gmail.com>
To: Mel Gorman <mel@csn.ul.ie>
Cc: Simon Kirby <sim@hostway.ca>,
        KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>,
        Shaohua Li <shaohua.li@intel.com>,
        Dave Hansen <dave@linux.vnet.ibm.com>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        linux-mm <linux-mm@kvack.org>,
        linux-kernel <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 4/6] mm: kswapd: Reset kswapd_max_order and
 classzone_idx after reading
Message-ID: <20101209155925.GD1740@barrios-desktop>
References: <1291893500-12342-1-git-send-email-mel@csn.ul.ie>
 <1291893500-12342-5-git-send-email-mel@csn.ul.ie>
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On Thu, Dec 09, 2010 at 11:18:18AM +0000, Mel Gorman wrote:
> When kswapd wakes up, it reads its order and classzone from pgdat and
> calls balance_pgdat. While its awake, it potentially reclaimes at a high
> order and a low classzone index. This might have been a once-off that
> was not required by subsequent callers. However, because the pgdat
> values were not reset, they remain artifically high while
> balance_pgdat() is running and potentially kswapd enters a second
> unnecessary reclaim cycle. Reset the pgdat order and classzone index
> after reading.
> 
> Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>

-- 
Kind regards,
Minchan Kim
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