From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754010Ab1HJMpO (ORCPT ); Wed, 10 Aug 2011 08:45:14 -0400 Received: from mx1.redhat.com ([209.132.183.28]:42318 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753312Ab1HJMpM (ORCPT ); Wed, 10 Aug 2011 08:45:12 -0400 Date: Wed, 10 Aug 2011 14:44:50 +0200 From: Johannes Weiner To: Mel Gorman Cc: Linux-MM , LKML , XFS , Dave Chinner , Christoph Hellwig , Wu Fengguang , Jan Kara , Rik van Riel , Minchan Kim Subject: Re: [PATCH 5/7] mm: vmscan: Do not writeback filesystem pages in kswapd except in high priority Message-ID: <20110810124450.GC24133@redhat.com> References: <1312973240-32576-1-git-send-email-mgorman@suse.de> <1312973240-32576-6-git-send-email-mgorman@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1312973240-32576-6-git-send-email-mgorman@suse.de> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Aug 10, 2011 at 11:47:18AM +0100, Mel Gorman wrote: > It is preferable that no dirty pages are dispatched for cleaning from > the page reclaim path. At normal priorities, this patch prevents kswapd > writing pages. > > However, page reclaim does have a requirement that pages be freed > in a particular zone. If it is failing to make sufficient progress > (reclaiming < SWAP_CLUSTER_MAX at any priority priority), the priority > is raised to scan more pages. A priority of DEF_PRIORITY - 3 is > considered to be the point where kswapd is getting into trouble > reclaiming pages. If this priority is reached, kswapd will dispatch > pages for writing. > > Signed-off-by: Mel Gorman > Reviewed-by: Minchan Kim Acked-by: Johannes Weiner