From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932867Ab2DKSPD (ORCPT ); Wed, 11 Apr 2012 14:15:03 -0400 Received: from mx1.redhat.com ([209.132.183.28]:58576 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752081Ab2DKSPB (ORCPT ); Wed, 11 Apr 2012 14:15:01 -0400 Message-ID: <4F85BEB5.6080702@redhat.com> Date: Wed, 11 Apr 2012 13:26:13 -0400 From: Rik van Riel User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:10.0.1) Gecko/20120216 Thunderbird/10.0.1 MIME-Version: 1.0 To: Mel Gorman CC: Andrew Morton , Konstantin Khlebnikov , Hugh Dickins , Ying Han , Linux-MM , LKML Subject: Re: [PATCH 2/3] mm: vmscan: Do not stall on writeback during memory compaction References: <1334162298-18942-1-git-send-email-mgorman@suse.de> <1334162298-18942-3-git-send-email-mgorman@suse.de> In-Reply-To: <1334162298-18942-3-git-send-email-mgorman@suse.de> 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 On 04/11/2012 12:38 PM, Mel Gorman wrote: > This patch stops reclaim/compaction entering sync reclaim as this was only > intended for lumpy reclaim and an oversight. Page migration has its own > logic for stalling on writeback pages if necessary and memory compaction > is already using it. > > Waiting on page writeback is bad for a number of reasons but the primary > one is that waiting on writeback to a slow device like USB can take a > considerable length of time. Page reclaim instead uses wait_iff_congested() > to throttle if too many dirty pages are being scanned. > > Signed-off-by: Mel Gorman Acked-by: Rik van Riel