From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail202.messagelabs.com (mail202.messagelabs.com [216.82.254.227]) by kanga.kvack.org (Postfix) with SMTP id 8A9F66B004D for ; Fri, 13 Nov 2009 13:37:47 -0500 (EST) Message-ID: <4AFDA724.7010200@redhat.com> Date: Fri, 13 Nov 2009 13:36:20 -0500 From: Rik van Riel MIME-Version: 1.0 Subject: Re: [PATCH] vmscan: Stop kswapd waiting on congestion when the min watermark is not being met References: <20091113142608.33B9.A69D9226@jp.fujitsu.com> <20091113135443.GF29804@csn.ul.ie> <20091114023138.3DA5.A69D9226@jp.fujitsu.com> <20091113181557.GM29804@csn.ul.ie> In-Reply-To: <20091113181557.GM29804@csn.ul.ie> Content-Type: text/plain; charset=ISO-8859-15; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: Mel Gorman Cc: Andrew Morton , KOSAKI Motohiro , Frans Pop , Jiri Kosina , Sven Geggus , Karol Lewandowski , Tobias Oetiker , linux-kernel@vger.kernel.org, "linux-mm@kvack.org" , Pekka Enberg , Christoph Lameter , Stephan von Krawczynski , "Rafael J. Wysocki" , Kernel Testers List List-ID: On 11/13/2009 01:15 PM, Mel Gorman wrote: > If reclaim fails to make sufficient progress, the priority is raised. > Once the priority is higher, kswapd starts waiting on congestion. However, > if the zone is below the min watermark then kswapd needs to continue working > without delay as there is a danger of an increased rate of GFP_ATOMIC > allocation failure. > > This patch changes the conditions under which kswapd waits on > congestion by only going to sleep if the min watermarks are being met. > > > diff --git a/mm/vmstat.c b/mm/vmstat.c > index 90b11e4..bc09547 100644 > --- a/mm/vmstat.c > +++ b/mm/vmstat.c > @@ -685,6 +685,7 @@ static const char * const vmstat_text[] = { > "kswapd_inodesteal", > "kswapd_slept_prematurely_fast", > "kswapd_slept_prematurely_slow", > + "kswapd_no_congestion_wait", > > Perhaps better named "kswapd_skip_congestion_wait" ? Other than that, the patch looks good to me. Reviewed-by: Rik van Riel -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org