From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chris Mason Subject: Re: reiserfs on removable media Date: 02 Jul 2003 14:59:05 -0400 Message-ID: <1057172345.20904.923.camel@tiny.suse.com> References: <20030702124544.Z7414@schatzie.adilger.int> <3F032A33.3050303@namesys.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: list-help: list-unsubscribe: list-post: Errors-To: flx@namesys.com In-Reply-To: <3F032A33.3050303@namesys.com> List-Id: Content-Type: text/plain; charset="us-ascii" To: Hans Reiser Cc: Andreas Dilger , Zygo Blaxell , reiserfs-list@namesys.com On Wed, 2003-07-02 at 14:53, Hans Reiser wrote: > >This is called ordered data mode, and exists on ext3 and also reiserfs with > >Chris Mason's patches. Under normal usage it shouldn't change performance > >compared to writeback data mode (which is what reiserfs does by default). > > > It had some impact, I forget exactly how much, maybe Chris can > resuscitate his benchmark of it? > The major cost of data=ordered is that dirty blocks are flushed every 5 seconds instead of every 30. The journal header patch in my experimental data logging directory changes things so that only new bytes in the file are done in data=ordered mode (either adding a new block or appending onto the end of the file). This helps a lot in the file rewrite tests. -chris