From owner-freebsd-hardware Tue Dec 31 13:51:19 2002 Delivered-To: freebsd-hardware@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 7161737B401; Tue, 31 Dec 2002 13:51:17 -0800 (PST) Received: from level.uwaterloo.ca (level.uwaterloo.ca [129.97.50.219]) by mx1.FreeBSD.org (Postfix) with ESMTP id 9D7B043EC5; Tue, 31 Dec 2002 13:51:16 -0800 (PST) (envelope-from bruce@engmail.uwaterloo.ca) Received: from level.uwaterloo.ca (localhost [127.0.0.1]) by level.uwaterloo.ca (8.12.3/8.12.3) with ESMTP id gBVLnw5n047159; Tue, 31 Dec 2002 16:49:58 -0500 (EST) (envelope-from bruce@engmail.uwaterloo.ca) Received: (from www@localhost) by level.uwaterloo.ca (8.12.3/8.12.3/Submit) id gBVLnv1N047158; Tue, 31 Dec 2002 16:49:57 -0500 (EST) X-Authentication-Warning: level.uwaterloo.ca: www set sender to bruce@engmail.uwaterloo.ca using -f Received: from 65.93.103.72 ( [65.93.103.72]) as user bruce@engmail.uwaterloo.ca by www.nexusmail.uwaterloo.ca with HTTP; Tue, 31 Dec 2002 16:49:57 -0500 Message-ID: <1041371397.3e121105cdf30@www.nexusmail.uwaterloo.ca> Date: Tue, 31 Dec 2002 16:49:57 -0500 From: Bruce Campbell To: Matthew Emmerton Cc: freebsd-hardware@FreeBSD.ORG, freebsd-questions@FreeBSD.ORG, sos@FreeBSD.ORG Subject: Re: ata "fallback to PIO mode" on dual processor AMD systems References: <1041368236.3e1204ac45da5@www.nexusmail.uwaterloo.ca> <025701c2b112$ddfbf580$1200a8c0@gsicomp.on.ca> In-Reply-To: <025701c2b112$ddfbf580$1200a8c0@gsicomp.on.ca> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8bit User-Agent: Internet Messaging Program (IMP) 3.1 / FreeBSD-4.6.2 X-Originating-IP: 65.93.103.72 Sender: owner-freebsd-hardware@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.org Quoting Matthew Emmerton : > [ cc'ing Soren since he's the ATA guru ] > > > Dec 30 23:27:00 ecserv13 /kernel: ad0: trying fallback to PIO mode > > Dec 30 23:27:00 ecserv13 /kernel: ata0: resetting devices .. done > > > > The test continues to run with the ata controller in PIO mode, with > > slower performance, and higher load average. > > > > Once the master drops to PIO, attempts to access the slave then cause > > it to drop to PIO. > > Are you using 80-conductor cables on all your drives? These are required to > get consistent high throughput, and running without them may cause the > problems you're seeing. Thanks for the information about the design of IDE etc, and the suggestion about the cables. I was about to shuffle things to get the disks onto separate channels, but I now see that would be a mistake as my CD drive would share a cable with a disk. Anyway, they all have the 80 conductor cable. I forgot to add some environmental and other information. The 4 AMD systems are in Aopen hx08 towers, with 400 watt power supplies, and 5 auxilliary fans (in addition to the power supply fan, and fan on each cpu). They are in an air conditioned machine room. The CPU and motherboard temperatures are within spec. I mention this as I note many reported AMD system problems traced to overheating. All drives are installed in removeable drive bays. I don't have the make/model on hand right now. They were $19 CAD. ($13USD). The low cost makes me suspicious now, but... I'm running the same tests on 4 single processor 2.4GHz Intel systems. They have not failed in this manner so far. Initially, I had 1GB memory modules in the AMD systems (I can't remember the make) and the systems froze and rebooted randomly. I moved to Crucial 512MB modules to cure that problem. ---------------------------------------- This mail sent through www.mywaterloo.ca To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hardware" in the body of the message