Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Sun, 4 Nov 2001 15:44:26 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Sun, 4 Nov 2001 15:44:17 -0500 Received: from mail.scsiguy.com ([63.229.232.106]:28433 "EHLO aslan.scsiguy.com") by vger.kernel.org with ESMTP id ; Sun, 4 Nov 2001 15:43:57 -0500 Message-Id: <200111042043.fA4KhpY70612@aslan.scsiguy.com> To: Stephan von Krawczynski cc: linux-kernel@vger.kernel.org, groudier@club-internet.fr Subject: Re: Adaptec vs Symbios performance In-Reply-To: Your message of "Sun, 04 Nov 2001 20:56:58 +0100." <20011104205658.3ac97e2d.skraw@ithnet.com> Date: Sun, 04 Nov 2001 13:43:51 -0700 From: "Justin T. Gibbs" Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org >See: > >Date: Wed, 31 Oct 2001 16:45:39 +0100 >From: Stephan von Krawczynski >To: linux-kernel >Subject: The good, the bad & the ugly (or VM, block devices, and SCSI :-) >Message-Id: <20011031164539.29c04ee0.skraw@ithnet.com> I don't read all of the LK list and the mail was not cc'd to me, so I did not see this thread. >> A full dmesg would be better. Right now I have no idea what kind >> of aic7xxx controller you are using, > >Adaptec A29160 (see above mail). Remarkably is I have a 32 bit PCI bus, no 64 >bit. This is an Asus CUV4X-D board. *Please stop editing things*. I need the actual boot messages from the detection of the aic7xxx card. It would also be nice to see the output of /proc/scsi/aic7xxx/ >> the speed and type of CPU, > >2 x PIII 1GHz Dmesg please. >Sorry, misunderstanding. What I meant was: how fast can you read data >from your cd-rom attached to some adaptec controller? I'll run some tests tomorrow at work. I'm sure the results will be dependent on the cdrom in question but they may show something. >> >If you redo this test with nfs-load (copy files from some client to your >> >test-box acting as nfs-server) you will end up at 1926 - 2631 kB/s >throughput >> >with aic, but 3395 - 3605 kB/s with symbios. >> >> What is the interrupt load during these tests? > >How can I present you an exact figure on this? Isn't there a systat or vmstat equivalent under Linux that gives you interrupt rates? I'll poke around tomorrow when I'm in front of a Linux box. >> Have you verified that >> disconnection is enabled for all devices on the aic7xxx controller? > >yes. The driver may not be seeing the same things as SCSI-Select for some strange reason. Again, just email me a full dmesg after a successful boot along with the /proc/scsi/aic7xxx/ output. >> This does not look like an interrupt latency problem. > >Based on which thoughts? It really looks like a bug in the driver's round-robin code or perhaps a difference in how many transactions we allow to be queued in the untagged case. Can you re-run your tests with the output directed to /dev/null for cdrom reads and also perform some benchmarks against your disk? The benchmarks should operate on one device only at a time with as little I/O to any other device during the test. -- Justin - 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/