From owner-freebsd-stable@FreeBSD.ORG Mon Aug 11 09:40:11 2003 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 3079637B404 for ; Mon, 11 Aug 2003 09:40:11 -0700 (PDT) Received: from mail.boulderlabs.com (mail.boulderlabs.com [206.168.112.48]) by mx1.FreeBSD.org (Postfix) with ESMTP id 7778243FBF for ; Mon, 11 Aug 2003 09:40:10 -0700 (PDT) (envelope-from bob@mail.boulderlabs.com) Received: from vec.boulderlabs.com (cpe-24-221-212-162.co.sprintbbd.net [24.221.212.162])h7BGe6ms024209; Mon, 11 Aug 2003 10:40:07 -0600 (MDT) (envelope-from bob@mail.boulderlabs.com) Received: from vec.boulderlabs.com (localhost.boulderlabs.com [127.0.0.1]) by vec.boulderlabs.com (8.12.2/8.12.2) with ESMTP id h7BGdvIL024267; Mon, 11 Aug 2003 10:39:58 -0600 (MDT) (envelope-from bob@vec.boulderlabs.com) Message-Id: <200308111639.h7BGdvIL024267@vec.boulderlabs.com> From: Robert Gray To: Wes Peters In-reply-to: Your message of "Sun, 10 Aug 2003 23:31:57 PDT." Date: Mon, 11 Aug 2003 10:39:56 -0600 Sender: bob@boulderlabs.com X-Spam-Status: No, hits=-5.5 required=5.0 tests=IN_REP_TO,QUOTED_EMAIL_TEXT,SPAM_PHRASE_00_01 version=2.41 cc: Daniela cc: stable@freebsd.org Subject: Re: Strange things going on with 4.8 X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 11 Aug 2003 16:40:11 -0000 I'd like to emphasize that memtest86 doesn't catch lots of memory problems. Just last week I was having trouble compiling mozilla so I ran memtest86 over night. Nothing showed up. But, "make buildworld" repeatedly failed on compiler signal 11 errors at about 20% complete. Using "make buildworld", I was able to isolate a bad DIMM and now "make buildworld" and building mozilla run to completion (multiple times). Whenever possible, I run with parity/ECC on the motherboard and the memory modules. I'm hoping a hardware/memory/motherboard expert will chime in. How can manufacturers continue to make PCs without memory checking? With today's standards of 128-256MB in a PC, isn't it just a matter of time until a bit gets flipped the wrong way? Are manufacturers hoping that the bad bit will go unnoticed in multi-media? Is there something in today's non-parity memory modules that helps insure reliable data? Until I hear otherwise, I'll continue to spend extra for the redundant, error-checking memories. Thanks -robert gray Wes Peters Sun, 10 Aug 2003 23:31:57 PDT says: >> >> Well the problem with testing memory with software is that its not >> necessarily possible to hammer it hard enough to trigger the problem. >> If you can reproduce it easily you might try cycling out one dimm and >> then trying to crash it. If removing a dimm fixes it then you probably >> took out the bad one. > >In fact, many people in the FreeBSD community feel the best memory test of >all is to 'make world' several times. I have experienced this myself >only once, but after returning the SIMM module to the vendor he verified >it was bad using a hardware tester. The replacement SIMM has been in for >5 months now and the machine has been marvelously stable, as I expect >from FreeBSD.