From owner-freebsd-questions@FreeBSD.ORG Mon Jun 14 18:20:11 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 4B84116A4CF for ; Mon, 14 Jun 2004 18:20:11 +0000 (GMT) Received: from pi.codefab.com (pi.codefab.com [199.103.21.227]) by mx1.FreeBSD.org (Postfix) with ESMTP id EB6F143D54 for ; Mon, 14 Jun 2004 18:20:10 +0000 (GMT) (envelope-from cswiger@mac.com) Received: from [10.1.1.193] (nfw1.codefab.com [199.103.21.225]) by pi.codefab.com (8.12.11/8.12.11) with ESMTP id i5EIJnHd098779; Mon, 14 Jun 2004 14:19:49 -0400 (EDT) In-Reply-To: References: <1086992110.17427.117.camel@Mandarin> Mime-Version: 1.0 (Apple Message framework v618) Content-Type: text/plain; charset=US-ASCII; format=flowed Message-Id: <6C183DA4-BE2F-11D8-BD27-003065ABFD92@mac.com> Content-Transfer-Encoding: 7bit From: Charles Swiger Date: Mon, 14 Jun 2004 14:19:49 -0400 To: Derrick MacPherson X-Mailer: Apple Mail (2.618) X-Spam-Status: No, hits=0.0 required=5.5 tests=none autolearn=no version=2.63 X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on pi.codefab.com cc: freebsd-questions@freebsd.org Subject: Re: FreeBSD 4-10 install, RAM parity errors that don't seem to happen inLinux. 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: Mon, 14 Jun 2004 18:20:11 -0000 On Jun 14, 2004, at 1:38 PM, Derrick MacPherson wrote: > Derrick MacPherson mainframe.ca> writes: >> I am trying to move as much of our servers as I can to FreeBSD, and >> there's a few boxes that they have here that the RAM is a about 2 mm >> high and requires the case (1U machines) to press on the RAM when >> closed. These machines run RH Linux for months without a problem, yet >> 3 >> out of 4 I just pulled are giving RAM parity problems during FreeBSD >> instalation. >> >> Does FreeBSD not allow/recover from those types of errors the same way >> Linux does? Any solutions? > > I posted this last week and hadn't seen a repsonse to it, is there > someone that > cares to take a poke at this? Well, if you are using ECC, normally they will correct all single-bit errors and notice but not correct larger multibit errors. This is done at a fairly low level in the hardware (which is why the BIOS typically controls the use of ECC), and is not something that is supposed to vary depending on which OS you are using. That being said, Linux and FreeBSD might be using different portions of memory which hit different RAM chips, and so you see the errors for one and not the other, but if you've got failing RAM, your systems are not going to be stable under heavy load regardless of what OS you use. I would expect you to see signs of problems under Linux, too, but consider running memtest86 for a day or so and see what you see: http://www.memtest86.com/ -- -Chuck