From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Wed, 29 Aug 2001 12:45:50 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Wed, 29 Aug 2001 12:45:41 -0400 Received: from archive.osdlab.org ([65.201.151.11]:17388 "EHLO fire.osdlab.org") by vger.kernel.org with ESMTP id ; Wed, 29 Aug 2001 12:45:28 -0400 Message-ID: <3B8D1ABF.4ED398DA@osdlab.org> Date: Wed, 29 Aug 2001 09:39:27 -0700 From: "Randy.Dunlap" Organization: OSDL X-Mailer: Mozilla 4.77 [en] (X11; U; Linux 2.4.3-20mdk i686) X-Accept-Language: en MIME-Version: 1.0 To: habanero@us.ibm.com CC: "linux-kernel@vger.kernel.org" , linux-fsdevel@vger.kernel.org Subject: Re: Journal FS Comparison on IOzone (was Netbench) In-Reply-To: <3B8A6122.3C784F2D@us.ibm.com> <3B8A9070.AD43D0E7@osdlab.org> <200108271929.OAA23048@popmail.austin.ibm.com> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Andrew Theurer wrote: > > On Monday 27 August 2001 01:24 pm, Randy.Dunlap wrote: > > Hi, > > > > I am doing some similar FS comparisons, but using IOzone > > (www.iozone.org) instead of Netbench. > > > > Some preliminary (mostly raw) data are available at: > > http://www.osdlab.org/reports/journal_fs/ > > (updated today). > > > > I am using a Linux 2.4.7 on a 4-way VA Linux system. > > It has 4 GB of RAM, but I have limited it to 256 MB in > > accordance with IOzone run rules. > > > > However, I suspect that this causes IOzone to measure disk > > subsystem or PCI bus performance more than it does FS performance. > > Any comments on this? > > Randy, > > You are definitly exceeding what the kernel will cache and writing to disk on > some tests. I guess it depends on what is more important to you. I think > both are valid things to test, and you may want to try not limiting memory to > get just FS performace in memory for large files. However, writing to disk > is important, especially for things like bounce-buffer. Did you have himem > support in your kernel? If so, did you have a bounce-buffer elimination > patch as well? Hi- Sorry about the delay in responding. I'm interested in filesystem performance. I'm not trying to document IDE vs. SCSI vs. FC performance/price tradeoffs, benefits, etc. > Does the storage system/controller have a disk cache? What size? Good questions, but I'm having trouble finding answers for them. (hence the delay in responding) The FC host controller is a QLogic 2200. It is attached to an IBM FAStT controller/drive array -- one controller with 10 attached drives. I've been looking at the IBM FAStT OS console interface, but I can't see much cache info there. There is one item: cache/processor sizes: 88/40 MB > Also, does IOzone default to num procs=num cpus? I didn't see any options in > your cmdline for num_procs. No, IOzone doesn't default to num_processes = num_cpus. That's a command-line option that I didn't use, although I expect to do some testing with that option also. Thanks for your comments. ~Randy