From: Michael Rubin Subject: Re: Problem with ext4_sync_file in no-journal mode. Date: Wed, 26 Aug 2009 15:30:53 -0700 Message-ID: <532480950908261530p2113b0cct22abf1f5ee0c0f2a@mail.gmail.com> References: <1251222245.20219.25.camel@bobble.smo.corp.google.com> <20090826162737.GB28867@atrey.karlin.mff.cuni.cz> <1251304886.23722.6.camel@bobble.smo.corp.google.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: Jan Kara , linux-ext4@vger.kernel.org To: fmayhar@google.com Return-path: Received: from smtp-out.google.com ([216.239.45.13]:52819 "EHLO smtp-out.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753958AbZHZWbP convert rfc822-to-8bit (ORCPT ); Wed, 26 Aug 2009 18:31:15 -0400 Received: from zps36.corp.google.com (zps36.corp.google.com [172.25.146.36]) by smtp-out.google.com with ESMTP id n7QMVGjW008132 for ; Wed, 26 Aug 2009 15:31:16 -0700 Received: from vws38 (vws38.prod.google.com [10.241.21.166]) by zps36.corp.google.com with ESMTP id n7QMUTGj022966 for ; Wed, 26 Aug 2009 15:31:13 -0700 Received: by vws38 with SMTP id 38so433230vws.16 for ; Wed, 26 Aug 2009 15:31:13 -0700 (PDT) In-Reply-To: <1251304886.23722.6.camel@bobble.smo.corp.google.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: On Wed, Aug 26, 2009 at 9:41 AM, Frank Mayhar wrote= : > That's what you would think, isn't it? =A0However, you (and we) would= be > wrong. =A0In our testing, ext4+fsync was significantly worse than ext= 4 > without fsync. =A0Like, six times worse. =A0Yes, this is a nonintuiti= ve > result and no, I can't yet explain it. =46rank is referring to (ext4 with no_journal)+fsync compared to ext4 with no journal and no fsync. With the journal everything is working as reliably as expected. We will be publishing data for all the permutations of crashes and power cycles we have tested as soon as we are confident in all the data. mrubin -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html