From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from relay.sgi.com (relay3.corp.sgi.com [198.149.34.15]) by oss.sgi.com (8.14.3/8.14.3/SuSE Linux 0.8) with ESMTP id o6DJnrVB105280 for ; Tue, 13 Jul 2010 14:49:53 -0500 Subject: Re: [PATCH] xfs: remove incorrect log write optimization From: Alex Elder In-Reply-To: <20100712160450.GA2666@infradead.org> References: <20100628143434.GA5473@infradead.org> <1278905400.7456.14.camel@doink> <20100712160450.GA2666@infradead.org> Date: Tue, 13 Jul 2010 14:52:45 -0500 Message-ID: <1279050765.1963.28.camel@doink> Mime-Version: 1.0 Reply-To: aelder@sgi.com 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: Christoph Hellwig Cc: xfs@oss.sgi.com On Mon, 2010-07-12 at 12:04 -0400, Christoph Hellwig wrote: > On Sun, Jul 11, 2010 at 10:30:00PM -0500, Alex Elder wrote: > > On Mon, 2010-06-28 at 10:34 -0400, Christoph Hellwig wrote: > > > We do need a barrier for the first buffer of a split log write. Otherwise > > > we might incorrectly stamp the tail LSN into transactions in the first > > > block, or not flush data I/O before updating the inode size. > > > > I'm not sure whether "first block" means the one at the beginning > > of the log, or the one at the beginning of a split log write. > > It means beginning of the split write. I can fix up the commit message > if you want. > Don't bother, I will change it to: We do need a barrier for the first buffer of a split log write. Otherwise we might incorrectly stamp the tail LSN into transactions in the first part of the split write, or not flush data I/O before updating the inode size. _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs