From: "Bill Rugolsky Jr." Subject: Re: Fw: Re: ICP, 3ware, Areca? Date: Tue, 7 Nov 2006 17:20:11 -0500 Message-ID: <20061107222011.GH29071@ti64.telemetry-investments.com> References: <20061107114724.9c2cc644.akpm@osdl.org> <1162933193.8123.36.camel@kleikamp.austin.ibm.com> <20061107134513.fbd5f219.akpm@osdl.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Dave Kleikamp , "linux-ext4@vger.kernel.org" Return-path: Received: from gw1a.telemetry-investments.com ([64.20.161.180]:44492 "EHLO sv1.telemetry-investments.com") by vger.kernel.org with ESMTP id S1752969AbWKGWUM (ORCPT ); Tue, 7 Nov 2006 17:20:12 -0500 To: Andrew Morton Content-Disposition: inline In-Reply-To: <20061107134513.fbd5f219.akpm@osdl.org> Sender: linux-ext4-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org On Tue, Nov 07, 2006 at 01:45:13PM -0800, Andrew Morton wrote: > On Tue, 07 Nov 2006 14:59:52 -0600 > Dave Kleikamp wrote: > > > On Tue, 2006-11-07 at 11:47 -0800, Andrew Morton wrote: > > > Why is ext3 slow?? > > > > Allocation? I don't see anything indicating that Bill is overwriting an > > existing file, so there is block allocation and journaling overhead. If > > that's the case, it would be interesting to see how fast ext3 is when > > overwriting a file. Extents and delayed allocation should improve on > > this a lot. Will do. > Maybe. or perhaps some funniness with RAID aligment. I neglected to include the relevant RAID/mkfs info here. device=/dev/sdc2 # ought to have been on a raid stripe boundary # very close to the start of the array # XFS: mkfs.xfs -f -d su=65536,sw=6 -l su=65536 $device mount -o noatime,attr2,largeio,logbsize=64k $device /mnt # Ext3: XFS has problems up through 2.6.18-rc5; use slow, but safe, Ext3: mke2fs -j -J size=400 -E stride=96 $device mount -o noatime $device /mnt Also, I ran blockdev --flushbufs and echo 1 | sudo tee /proc/sys/vm/drop_caches before each test. -Bill