From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754268Ab0KOJRe (ORCPT ); Mon, 15 Nov 2010 04:17:34 -0500 Received: from gir.skynet.ie ([193.1.99.77]:55329 "EHLO gir.skynet.ie" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752843Ab0KOJRd (ORCPT ); Mon, 15 Nov 2010 04:17:33 -0500 Date: Mon, 15 Nov 2010 09:17:19 +0000 From: Mel Gorman To: KOSAKI Motohiro Cc: Andrea Arcangeli , Andrew Morton , Rik van Riel , Johannes Weiner , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 3/3] mm,vmscan: Reclaim order-0 and compact instead of lumpy reclaim when under light pressure Message-ID: <20101115091719.GD27362@csn.ul.ie> References: <1289502424-12661-4-git-send-email-mel@csn.ul.ie> <20101112093742.GA3537@csn.ul.ie> <20101114144155.E01F.A69D9226@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: <20101114144155.E01F.A69D9226@jp.fujitsu.com> User-Agent: Mutt/1.5.17+20080114 (2008-01-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Nov 14, 2010 at 02:43:12PM +0900, KOSAKI Motohiro wrote: > > On Thu, Nov 11, 2010 at 07:07:04PM +0000, Mel Gorman wrote: > > > + if (COMPACTION_BUILD) > > > + sc->lumpy_reclaim_mode = LUMPY_MODE_COMPACTION; > > > + else > > > + sc->lumpy_reclaim_mode = LUMPY_MODE_CONTIGRECLAIM; > > > > > > > Gack, I posted the slightly wrong version. This version prevents lumpy > > reclaim ever being used. The figures I posted were for a patch where > > this condition looked like > > > > if (COMPACTION_BUILD && priority > DEF_PRIORITY - 2) > > sc->lumpy_reclaim_mode = LUMPY_MODE_COMPACTION; > > else > > sc->lumpy_reclaim_mode = LUMPY_MODE_CONTIGRECLAIM; > > In all other place, heavy reclaim detection are used folliowing. > > if (priority < DEF_PRIORITY - 2) > > > So, "priority >= DEF_PRIORITY - 2" is more symmetric, I think. but if you have strong > reason, I don't oppse. > I had no strong reason other than "I don't want lumpy reclaim to be used easily". I will match the other places. Thanks -- Mel Gorman Part-time Phd Student Linux Technology Center University of Limerick IBM Dublin Software Lab