Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S968731Ab0B1PgS (ORCPT ); Sun, 28 Feb 2010 10:36:18 -0500 Received: from mail.tmr.com ([64.65.253.246]:51689 "EHLO partygirl.tmr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S968708Ab0B1PgR (ORCPT ); Sun, 28 Feb 2010 10:36:17 -0500 Message-ID: <4B8A8D68.1020809@tmr.com> Date: Sun, 28 Feb 2010 10:36:08 -0500 From: Bill Davidsen Organization: TMR Associates Inc, Schenectady NY User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.8.1.21) Gecko/20090507 Fedora/1.1.16-1.fc9 NOT Firefox/3.0.11 SeaMonkey/1.1.16 MIME-Version: 1.0 To: Justin Piszcz CC: Mike Snitzer , Neil Brown , linux-kernel@vger.kernel.org, linux-raid@vger.kernel.org, linux-ext4@vger.kernel.org, Alan Piszcz Subject: Re: mdadm software raid + ext4, capped at ~350MiB/s limitation/bug? References: <20100228080100.092c24c2@notabene.brown> <4B89B44A.70005@tmr.com> <170fa0d21002280633x2ea6a281tf53996834c46d831@mail.gmail.com> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1757 Lines: 52 Justin Piszcz wrote: > > > On Sun, 28 Feb 2010, Mike Snitzer wrote: > >> On Sun, Feb 28, 2010 at 4:45 AM, Justin Piszcz >> wrote: > > [ .. ] > >> >> How did you format the ext3 and ext4 filesystems? >> >> Did you use mkfs.ext[34] -E stride and stripe-width accordingly? >> AFAIK even older versions of mkfs.xfs will probe for this info but >> older mkfs.ext[34] won't (though new versions of mkfs.ext[34] will, >> using the Linux "topology" info). > > Yes and it did not make any difference: > http://lkml.org/lkml/2010/2/27/77 > > Incase anyone else wants to try too, you can calculate by hand, or if you > are in a hurry, I found this useful: > http://busybox.net/~aldot/mkfs_stride.html > > I believe there is something fundamentally wrong with ext4 when > performing large sequential I/O when writing, esp. after Ted's comments. > > Justin. > > -- > To unsubscribe from this list: send the line "unsubscribe linux-raid" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > I'm going to have to do some testing now, I just tested ext4 against the raw speed of the device (single device test) and they were quite close to identical. I'm going to order one more drive to bring my test setup up to five devices, and do some testing on how it behaves. More later. -- Bill Davidsen "We can't solve today's problems by using the same thinking we used in creating them." - Einstein -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/