From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cuda.sgi.com (cuda2.sgi.com [192.48.176.25]) by oss.sgi.com (8.14.3/8.14.3/SuSE Linux 0.8) with ESMTP id p8KIaLQm076514 for ; Tue, 20 Sep 2011 13:36:21 -0500 Received: from mx1.redhat.com (localhost [127.0.0.1]) by cuda.sgi.com (Spam Firewall) with ESMTP id 47293177469 for ; Tue, 20 Sep 2011 11:36:20 -0700 (PDT) Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) by cuda.sgi.com with ESMTP id 28g1eXvf1wbu9s7F for ; Tue, 20 Sep 2011 11:36:20 -0700 (PDT) Message-ID: <4E78DD10.4000900@redhat.com> Date: Tue, 20 Sep 2011 14:36:00 -0400 From: Rik van Riel MIME-Version: 1.0 Subject: Re: [patch 2/4] mm: writeback: distribute write pages across allowable zones References: <1316526315-16801-1-git-send-email-jweiner@redhat.com> <1316526315-16801-3-git-send-email-jweiner@redhat.com> In-Reply-To: <1316526315-16801-3-git-send-email-jweiner@redhat.com> List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: xfs-bounces@oss.sgi.com Errors-To: xfs-bounces@oss.sgi.com To: Johannes Weiner Cc: linux-ext4@vger.kernel.org, Jan Kara , linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org, xfs@oss.sgi.com, Christoph Hellwig , linux-mm@kvack.org, Andreas Dilger , Mel Gorman , linux-fsdevel@vger.kernel.org, Theodore Ts'o , Andrew Morton , Wu Fengguang , Chris Mason , Minchan Kim On 09/20/2011 09:45 AM, Johannes Weiner wrote: > This patch allows allocators to pass __GFP_WRITE when they know in > advance that the allocated page will be written to and become dirty > soon. The page allocator will then attempt to distribute those > allocations across zones, such that no single zone will end up full of > dirty, and thus more or less, unreclaimable pages. > > The global dirty limits are put in proportion to the respective zone's > amount of dirtyable memory and allocations diverted to other zones > when the limit is reached. > > For now, the problem remains for NUMA configurations where the zones > allowed for allocation are in sum not big enough to trigger the global > dirty limits, but a future approach to solve this can reuse the > per-zone dirty limit infrastructure laid out in this patch to have > dirty throttling and the flusher threads consider individual zones. > > Signed-off-by: Johannes Weiner Reviewed-by: Rik van Riel The amount of work done in a __GFP_WRITE allocation looks a little daunting, but doing that a million times probably outweighs waiting on the disk even once, so... _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs