Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758113Ab1FAQDX (ORCPT ); Wed, 1 Jun 2011 12:03:23 -0400 Received: from mx1.redhat.com ([209.132.183.28]:5046 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757841Ab1FAQDW (ORCPT ); Wed, 1 Jun 2011 12:03:22 -0400 Message-ID: <4DE662BF.3000309@redhat.com> Date: Wed, 01 Jun 2011 12:03:11 -0400 From: Rik van Riel User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.7) Gecko/20100720 Fedora/3.1.1-1.fc13 Lightning/1.0b2pre Thunderbird/3.1.1 MIME-Version: 1.0 To: Minchan Kim CC: Andrew Morton , linux-mm , LKML , KAMEZAWA Hiroyuki , KOSAKI Motohiro , Mel Gorman , Andrea Arcangeli , Johannes Weiner Subject: Re: [PATCH v2 05/10] compaction: make isolate_lru_page with filter aware References: <4feb21bdac4c00a30f3c0d9361bd3565e6afa72f.1306689214.git.minchan.kim@gmail.com> In-Reply-To: <4feb21bdac4c00a30f3c0d9361bd3565e6afa72f.1306689214.git.minchan.kim@gmail.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1170 Lines: 26 On 05/29/2011 02:13 PM, Minchan Kim wrote: > In async mode, compaction doesn't migrate dirty or writeback pages. > So, it's meaningless to pick the page and re-add it to lru list. > > Of course, when we isolate the page in compaction, the page might > be dirty or writeback but when we try to migrate the page, the page > would be not dirty, writeback. So it could be migrated. But it's > very unlikely as isolate and migration cycle is much faster than > writeout. > > So, this patch helps cpu and prevent unnecessary LRU churning. > > Reviewed-by: KAMEZAWA Hiroyuki > Reviewed-by: KOSAKI Motohiro > Acked-by: Johannes Weiner > Acked-by: Mel Gorman > Cc: Rik van Riel > Cc: Andrea Arcangeli > Signed-off-by: Minchan Kim ACked-by: Rik van Riel -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/