From owner-freebsd-stable@FreeBSD.ORG Tue Jun 27 07:25:13 2006 Return-Path: X-Original-To: freebsd-stable@freebsd.org 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 CDF5316A401 for ; Tue, 27 Jun 2006 07:25:13 +0000 (UTC) (envelope-from dmitry@atlantis.dp.ua) Received: from postman.atlantis.dp.ua (postman.atlantis.dp.ua [193.108.47.1]) by mx1.FreeBSD.org (Postfix) with ESMTP id 0659D445B9 for ; Tue, 27 Jun 2006 07:25:12 +0000 (GMT) (envelope-from dmitry@atlantis.dp.ua) Received: from smtp.atlantis.dp.ua (smtp.atlantis.dp.ua [193.108.46.231]) by postman.atlantis.dp.ua (8.13.1/8.13.1) with ESMTP id k5R7P52J088189; Tue, 27 Jun 2006 10:25:05 +0300 (EEST) (envelope-from dmitry@atlantis.dp.ua) Date: Tue, 27 Jun 2006 10:25:05 +0300 (EEST) From: Dmitry Pryanishnikov To: Paul Allen In-Reply-To: <20060627004115.GA12597@groat.ugcs.caltech.edu> Message-ID: <20060627102111.I35218@atlantis.atlantis.dp.ua> References: <20060626081029.L1114@ganymede.hub.org> <20060626140333.M38418@fledge.watson.org> <20060626235355.Q95667@atlantis.atlantis.dp.ua> <44A04FD2.1030001@hirsch.it> <20060627011512.N95667@atlantis.atlantis.dp.ua> <44A06233.1090704@hirsch.it> <20060627014335.E87535@atlantis.atlantis.dp.ua> <44A068A7.3090403@hirsch.it> <20060627020819.L3403@atlantis.atlantis.dp.ua> <44A06FFB.40104@hirsch.it> <20060627004115.GA12597@groat.ugcs.caltech.edu> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Cc: "M.Hirsch" , freebsd-stable@freebsd.org Subject: Re: FreeBSD 6.x CVSUP today crashes with zero load ... X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 27 Jun 2006 07:25:13 -0000 On Mon, 26 Jun 2006, Paul Allen wrote: > The very originating purpose of ECC was to keep the computer going in the > face of an alpha particle strike. > > Alpha particles flip *single* bits. > > ECC was never intended to detect crummy, failing hardware: that's a use > people have shoe-horned it into, but for which it is not entirely suited. Well, correction is the last 'C' in ECC. Don't forget about second (and more significant): Check. Error Check actually detects failing memory chips (structure of the correcting code ensures detection of every 2-bit failure and most N-bit (N>2)). Sincerely, Dmitry -- Atlantis ISP, System Administrator e-mail: dmitry@atlantis.dp.ua nic-hdl: LYNX-RIPE