Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752602Ab0BRD6g (ORCPT ); Wed, 17 Feb 2010 22:58:36 -0500 Received: from mx1.redhat.com ([209.132.183.28]:21397 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751202Ab0BRD6e (ORCPT ); Wed, 17 Feb 2010 22:58:34 -0500 Message-ID: <4B7CBAB4.2010003@redhat.com> Date: Wed, 17 Feb 2010 22:57:40 -0500 From: Rik van Riel Organization: Red Hat, Inc User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.5) Gecko/20091209 Fedora/3.0-4.fc12 Lightning/1.0pre Thunderbird/3.0 MIME-Version: 1.0 To: Mel Gorman CC: Andrea Arcangeli , Christoph Lameter , Adam Litke , Avi Kivity , David Rientjes , KOSAKI Motohiro , linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH 08/12] Direct compact when a high-order allocation fails References: <1265976059-7459-1-git-send-email-mel@csn.ul.ie> <1265976059-7459-9-git-send-email-mel@csn.ul.ie> In-Reply-To: <1265976059-7459-9-git-send-email-mel@csn.ul.ie> Content-Type: text/plain; charset=UTF-8; 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: 1091 Lines: 24 On 02/12/2010 07:00 AM, Mel Gorman wrote: > Ordinarily when a high-order allocation fails, direct reclaim is entered to > free pages to satisfy the allocation. With this patch, it is determined if > an allocation failed due to external fragmentation instead of low memory > and if so, the calling process will compact until a suitable page is > freed. Compaction by moving pages in memory is considerably cheaper than > paging out to disk and works where there are locked pages or no swap. If > compaction fails to free a page of a suitable size, then reclaim will > still occur. > > Direct compaction returns as soon as possible. As each block is compacted, > it is checked if a suitable page has been freed and if so, it returns. > > Signed-off-by: Mel Gorman Acked-by: Rik van Riel -- All rights reversed. -- 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/