From: "Sidorov, Andrei" Subject: RE: ext4 file replace guarantees Date: Fri, 21 Jun 2013 21:49:26 +0000 Message-ID: References: <1371764058.18527.140661246414097.671B4999@webmail.messagingengine.com> <20130621005937.GB10730@thunk.org> <1371818596.20553.140661246775057.0F7160F3@webmail.messagingengine.com> <20130621131521.GE10730@thunk.org> <1371822707.3188.140661246795017.2D10645B@webmail.messagingengine.com> ,<20130621210556.GB10582@thunk.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT Cc: "linux-ext4@vger.kernel.org" , Ryan Lortie To: "Theodore Ts'o" , "Joseph D. Wagner" Return-path: Received: from mail.arrisi.com ([216.234.147.109]:51803 "EHLO mail.arrisi.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1946231Ab3FUXSd convert rfc822-to-8bit (ORCPT ); Fri, 21 Jun 2013 19:18:33 -0400 In-Reply-To: <20130621210556.GB10582@thunk.org> Content-Language: en-US Sender: linux-ext4-owner@vger.kernel.org List-ID: But there is no need to mount entire fs with data journalling mode. In fact I find per-file data journalling extremely useful. It would be even more useful if it allowed regular users to set journalling mode on specific file and there was some way to designate rewrite transaction boundaries (even 128k would cover a lot of small-but-important-file use cases). As for now it is a best choice for app running with root privileges for rewriting files <= page size. Regards, Andrey. ________________________________________ From: linux-ext4-owner@vger.kernel.org [linux-ext4-owner@vger.kernel.org] on behalf of Theodore Ts'o [tytso@mit.edu] Sent: Saturday, June 22, 2013 01:05 To: Joseph D. Wagner Cc: linux-ext4@vger.kernel.org; Ryan Lortie Subject: Re: ext4 file replace guarantees On Fri, Jun 21, 2013 at 09:25:13AM -0700, Joseph D. Wagner wrote: > > Please forgive me for the stupid question. Would Ryan's concerns be > addressed by configuring ext4 to run in data=journal mode? It would, but for most workloads, data=journal is much, much slower. - Ted