From: "Daniel Taylor" Subject: RE: inconsistent file placement Date: Tue, 6 Jul 2010 18:08:53 -0700 Message-ID: <469D2D911E4BF043BFC8AD32E8E30F5B24AEDF@wdscexbe07.sc.wdc.com> References: <469D2D911E4BF043BFC8AD32E8E30F5B24AED8@wdscexbe07.sc.wdc.com> <20100706185548.GA26677@thunk.org> <4C337D16.9000200@redhat.com> <469D2D911E4BF043BFC8AD32E8E30F5B24AEDB@wdscexbe07.sc.wdc.com> <20100706231412.GA7646@thunk.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT Cc: "Eric Sandeen" , , To: Return-path: Received: from wdscspam2.wdc.com ([129.253.170.131]:4481 "EHLO wdscspam2.wdc.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751274Ab0GGBSX convert rfc822-to-8bit (ORCPT ); Tue, 6 Jul 2010 21:18:23 -0400 Content-class: urn:content-classes:message In-Reply-To: <20100706231412.GA7646@thunk.org> Sender: linux-ext4-owner@vger.kernel.org List-ID: > -----Original Message----- > From: tytso@mit.edu [mailto:tytso@mit.edu] > Sent: Tuesday, July 06, 2010 4:14 PM > To: Daniel Taylor > Cc: Eric Sandeen; amir73il@gmail.com; linux-ext4@vger.kernel.org > Subject: Re: inconsistent file placement > > On Tue, Jul 06, 2010 at 03:15:00PM -0700, Daniel Taylor wrote: > > > > It is an unfortunate fact of life that simplistic benchmarks often > > drive sales. This product will be a consumer NAS and when our > > internal runs of the common NAS benchmarks get inconsistent results, > > it creates a lot of concern. > > Out of curiosity, what *are* the "common NAS benchmarks" in use today, > and who chooses them? The benchmarks are chosen by individual reviewers (probably looking over each others' shoulders). "smallnetbuilder.com" is a fairly good example. FWIW: 1) NASPT, PC only 2) IOzone, Mac & PC 3) IOmeter, PC BTW, the simple test sequence was trying to distill something that our in-house performance tester was seeing in some SATA traces. It is NOT one of the "real" benchmarks. > Speaking of fallocate.... if this is a NAS box than the file is > probably written using CIFS, right? Are you using a modern version of > Samba? Currently, we're on 3.2.5 of smdb, but that's because the later versions work less well with ext3. We will be testing them with ext4 now that we see the other options it offers. Soon as I can get the fallocate utility cross-built, there are some experiments that I want to run, but those will take a couple of days. Thanks again for all of your help.