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 q626WUwV174486 for ; Mon, 2 Jul 2012 01:32:31 -0500 Received: from bombadil.infradead.org (173-166-109-252-newengland.hfc.comcastbusiness.net [173.166.109.252]) by cuda.sgi.com with ESMTP id 628Xmx2ARpvro3oy (version=TLSv1 cipher=AES256-SHA bits=256 verify=NO) for ; Sun, 01 Jul 2012 23:32:30 -0700 (PDT) Date: Mon, 2 Jul 2012 02:32:26 -0400 From: Christoph Hellwig Subject: Re: [MMTests] IO metadata on XFS Message-ID: <20120702063226.GA32151@infradead.org> References: <20120620113252.GE4011@suse.de> <20120629111932.GA14154@suse.de> <20120629112505.GF14154@suse.de> <20120701235458.GM19223@dastard> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20120701235458.GM19223@dastard> 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: Dave Chinner Cc: linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, xfs@oss.sgi.com, Mel Gorman , linux-kernel@vger.kernel.org On Mon, Jul 02, 2012 at 09:54:58AM +1000, Dave Chinner wrote: > That will be caused by the fact we changed all the metadata updates > to be logged, which means a transaction every time .dirty_inode is > called. > > This should mostly go away when XFS is converted to use .update_time > rather than .dirty_inode to only issue transactions when the VFS > updates the atime rather than every .dirty_inode call... I think the patch to do that conversion still needs review.. > It increases the CPU overhead (dirty_inode can be called up to 4 > times per write(2) call, IIRC), so with limited numbers of > threads/limited CPU power it will result in lower performance. Where > you have lots of CPU power, there will be little difference in > performance... When I checked it it could only be called twice, and we'd already optimize away the second call. I'd defintively like to track down where the performance changes happend, at least to a major version but even better to a -rc or git commit. _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs