From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vivek Goyal Subject: Re: [dm-devel] [PATCH 1/3] dm: log writes target Date: Mon, 23 Mar 2015 14:02:45 -0400 Message-ID: <20150323180245.GE3172@redhat.com> References: <1426797070-27463-1-git-send-email-jbacik@fb.com> <1426797070-27463-2-git-send-email-jbacik@fb.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linux-btrfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, dm-devel@redhat.com, zab@redhat.com, fstests@vger.kernel.org To: Josef Bacik Return-path: Content-Disposition: inline In-Reply-To: <1426797070-27463-2-git-send-email-jbacik@fb.com> Sender: fstests-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org On Thu, Mar 19, 2015 at 04:31:08PM -0400, Josef Bacik wrote: [..] > + * We log writes only after they have been flushed, this makes the log describe > + * close to the order in which the data hits the actual disk, not its cache. So > + * for example the following sequence (W means write, C means complete) > + * > + * Wa,Wb,Wc,Cc,Ca,FLUSH,FUAd,Cb,CFLUSH,CFUAd > + * > + * Would result in the log looking like this > + * > + * c,a,flush,fuad,b,, > + * A minor nit, Should this sequence be following. c,a,b, flush,fuad,, when flush completed by that time write of b has completed too. So it should be written first? Thanks Vivek