From owner-freebsd-questions@FreeBSD.ORG Fri Dec 3 10:57:01 2004 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id C8D8E16A4CE for ; Fri, 3 Dec 2004 10:57:01 +0000 (GMT) Received: from szamoca.krvarr.bc.ca (s142-179-111-232.bc.hsia.telus.net [142.179.111.232]) by mx1.FreeBSD.org (Postfix) with ESMTP id 3FB6243D2F for ; Fri, 3 Dec 2004 10:56:59 +0000 (GMT) (envelope-from sandy@krvarr.bc.ca) Received: from szamoca.krvarr.bc.ca (localhost [127.0.0.1]) by szamoca.krvarr.bc.ca (8.13.1/8.12.11) with ESMTP id iB3AtQTr061280; Fri, 3 Dec 2004 02:55:26 -0800 (PST) (envelope-from sandy@szamoca.krvarr.bc.ca) Received: (from sandy@localhost) by szamoca.krvarr.bc.ca (8.13.1/8.12.11/Submit) id iB3AtLgG061277; Fri, 3 Dec 2004 02:55:21 -0800 (PST) (envelope-from sandy) From: Sandy Rutherford MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <16816.17945.240544.50782@szamoca.krvarr.bc.ca> Date: Fri, 3 Dec 2004 02:55:21 -0800 To: Chris Dillon In-Reply-To: <20041202122615.O40359@duey.wolves.k12.mo.us> References: <6FC9F9894A9F8C49A722CF9F2132FC220276581D@ms05.mailstreet2003.net> <20041125234948.R27818@april.chuckr.org> <20041202122615.O40359@duey.wolves.k12.mo.us> X-Mailer: VM 7.07 under Emacs 21.3.1 cc: Chuck Robey cc: "Haulmark, Chris" cc: Jonathon McKitrick cc: freebsd-questions@freebsd.org Subject: RE: Is this a sign of memory going bad? X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 03 Dec 2004 10:57:02 -0000 If the goal is simply to stress-test the memory, just take a huge file and write a shell script loop to gzip it and ungzip it ad infinitum. I used this technique a while ago to ferret out some memory problems. In this case, the bad memory manifested itself as gzip eventually reporting an error that the file was corrupted. I'm not saying that this is a fool-proof way of finding bad memory, but it did the job at the time. Sandy >>>>> On Thu, 2 Dec 2004 12:53:44 -0600 (CST), >>>>> Chris Dillon said: > On Thu, 25 Nov 2004, Chuck Robey wrote: >> I don't want to embarrass anyone here, but something needs to be >> said. Note this next sentence carefully: THERE IS NO SUCH THING AS A >> WORKING MEMORY TEST PROGRAM!!! >> .... > The memory-test programs are not entirely worthless. Just recently we > had a lab of PCs where some of them would go wonky and randomly lock > up hard. This was happening for months and we couldn't put our finger > on the problem. We thought maybe it was something in our Windows > build, so we tried booting Microsoft's stand-alone memory tester (yes, > they have one, and I'm not sure where I got it, MSDN perhaps?), very > similar to memtest86. After a random number of test passes, sometimes > 100+ passes (many hours, overnight), some of the machines would lock > up. No errors indicated, they just froze. Oops. Definately NOT a > software problem. After fiddling around with some of the > clock/voltage related BIOS settings, putting new thermal compound > between the CPUs and heatsinks, reseating cards and memory, placing > the PCs inside a hexagram drawn on the floor and dancing nak... > nevermind... we got them to run the tests continuously through our > entire 4-day Thanksgiving weekend without problems. For the last 4 > days (including today), we haven't had any problems with them. > So, these memtest programs can at least be valuable stress-testing > tools but be prepared to run them for hours or days at a time before > they will catch something. :-) > -- > Chris Dillon - cdillon(at)wolves.k12.mo.us > FreeBSD: The fastest, most open, and most stable OS on the planet > - Available for IA32, IA64, AMD64, PC98, Alpha, and UltraSPARC architectures > - PowerPC, ARM, MIPS, and S/390 under development > - http://www.freebsd.org > Q: Because it reverses the logical flow of conversation. > A: Why is putting a reply at the top of the message frowned upon? > _______________________________________________ > freebsd-questions@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-questions > To unsubscribe, send any mail to "freebsd-questions-unsubscribe@freebsd.org"