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 oAU0xJ57251693 for ; Mon, 29 Nov 2010 18:59:19 -0600 Received: from mail.internode.on.net (localhost [127.0.0.1]) by cuda.sgi.com (Spam Firewall) with ESMTP id 2B29A1C8089E for ; Mon, 29 Nov 2010 17:00:59 -0800 (PST) Received: from mail.internode.on.net (bld-mail20.adl6.internode.on.net [150.101.137.105]) by cuda.sgi.com with ESMTP id 5rE339iNEbtD41dJ for ; Mon, 29 Nov 2010 17:00:59 -0800 (PST) Date: Tue, 30 Nov 2010 12:00:50 +1100 From: Dave Chinner Subject: Re: [PATCH 2/2] xfs: don't truncate prealloc from frequently accessed inodes Message-ID: <20101130010050.GA3556@dastard> References: <1290991431-20519-1-git-send-email-david@fromorbit.com> <1290991431-20519-3-git-send-email-david@fromorbit.com> <87vd3glb3u.fsf@basil.nowhere.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <87vd3glb3u.fsf@basil.nowhere.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: Andi Kleen Cc: linux-fsdevel@vger.kernel.org, xfs@oss.sgi.com On Mon, Nov 29, 2010 at 10:42:29AM +0100, Andi Kleen wrote: > Dave Chinner writes: > > > > To avoid this problem, keep a count of the number of ->release calls > > made on an inode. For most cases, an inode is only going to be opened > > once for writing and then closed again during it's lifetime in > > cache. Hence if there are multiple ->release calls, there is a good > > chance that the inode is being accessed by the NFS server. Hence > > count up every time ->release is called while there are delalloc > > blocks still outstanding on the inode. > > Seems like a hack. It would be cleaner and less fragile to add a > explicit VFS hint that is passed down from the nfs server, similar > to the existing open intents. Agreed. However, we've been asking for the nfsd to change it's behaviour for various operations for quite some time (i.e. years) to help filesystems behave better, but and we're no closer to having it fixed now than we were 3 or 4 years ago. What the nfsd really needs is an an open file cache so that IO looks like normal file IO rather than every write being an "open-write-close" operation.... While we wait for nfsd to be fixed, we've still got people reporting excessive fragmentation during concurrent sequential writes to nfs servers running XFS, so we really need some kind of fix for the problem... Cheers, Dave. -- Dave Chinner david@fromorbit.com _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs