From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cuda.sgi.com (cuda3.sgi.com [192.48.176.15]) by oss.sgi.com (8.14.3/8.14.3/SuSE Linux 0.8) with ESMTP id o91E1oYL080551 for ; Fri, 1 Oct 2010 09:01:50 -0500 Received: from mail.internode.on.net (localhost [127.0.0.1]) by cuda.sgi.com (Spam Firewall) with ESMTP id 9B9F31E72D4A for ; Fri, 1 Oct 2010 07:02:49 -0700 (PDT) Received: from mail.internode.on.net (bld-mail12.adl6.internode.on.net [150.101.137.97]) by cuda.sgi.com with ESMTP id 48LktbxfBpsYXqqj for ; Fri, 01 Oct 2010 07:02:49 -0700 (PDT) Date: Sat, 2 Oct 2010 00:02:37 +1000 From: Dave Chinner Subject: Re: [patch] xfs: properly account for reclaimed inodes Message-ID: <20101001140237.GC4681@dastard> References: <20101001074354.GF2618@cmpxchg.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20101001074354.GF2618@cmpxchg.org> List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: xfs-bounces@oss.sgi.com Errors-To: xfs-bounces@oss.sgi.com To: Johannes Weiner Cc: stable@kernel.org, John Hawley , linux-kernel@vger.kernel.org, xfs@oss.sgi.com On Fri, Oct 01, 2010 at 09:43:54AM +0200, Johannes Weiner wrote: > When marking an inode reclaimable, a per-AG counter is increased, the > inode is tagged reclaimable in its per-AG tree, and, when this is the > first reclaimable inode in the AG, the AG entry in the per-mount tree > is also tagged. > > When an inode is finally reclaimed, however, it is only deleted from > the per-AG tree. Neither the counter is decreased, nor is the parent > tree's AG entry untagged properly. > > Since the tags in the per-mount tree are not cleared, the inode > shrinker iterates over all AGs that have had reclaimable inodes at one > point in time. > > The counters on the other hand signal an increasing amount of slab > objects to reclaim. Since "70e60ce xfs: convert inode shrinker to > per-filesystem context" this is not a real issue anymore because the > shrinker bails out after one iteration. > > But the problem was observable on a machine running v2.6.34, where the > reclaimable work increased and each process going into direct reclaim > eventually got stuck on the xfs inode shrinking path, trying to scan > several million objects. > > Fix this by properly unwinding the reclaimable-state tracking of an > inode when it is reclaimed. > > Signed-off-by: Johannes Weiner > Cc: stable@kernel.org Looks OK to me, and has run through a few hours of testing without problems. Reviewed-by: Dave Chinner Cheers, Dave. -- Dave Chinner david@fromorbit.com _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs