From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Thu, 24 May 2001 13:31:45 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Thu, 24 May 2001 13:31:35 -0400 Received: from fmfdns02.fm.intel.com ([132.233.247.11]:29174 "EHLO thalia.fm.intel.com") by vger.kernel.org with ESMTP id ; Thu, 24 May 2001 13:31:22 -0400 Message-ID: <9678C2B4D848D41187450090276D1FAE0635F05A@FMSMSX32> From: "Cress, Andrew R" To: "'Jonathan Lundell'" , Jens Axboe , Andi Kleen Cc: Andreas Dilger , monkeyiq , linux-kernel@vger.kernel.org Subject: RE: Dying disk and filesystem choice. Date: Thu, 24 May 2001 10:30:43 -0700 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2653.19) Content-Type: text/plain; charset="iso-8859-1" Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org >At 12:19 PM +0200 2001-05-24, Jens Axboe wrote: >>In fact you will typically only see an I/O error if the drive _can't_ >>remap the sector anymore, because it has run out. No point in reporting >>a condition that was recovered. >> >>I'd still say, that if you get bad block errors reported from your disk >>it's long overdue for replacement. On Thursday, May 24, 2001 11:46 AM, Jonathan Lundell wrote: >This can't be right. It implies that the drive is returning bogus >data with no error indication. Remapping a bad sector is not the same >as recovering it. The automatic reallocation of bad spots on a drive is safe unless paired with the write cache enabled bit in the disk mode pages (configuration). WCE, in some cases, can cause the write/read to both take place from cache with good status, and if the bad spot is reallocated later, when the cache is flushed, the reporting gets very confusing. In general: It is a common misconception that if a disk begins to show some bad spots, that it should be replaced. In fact, a disk can have a reliable, useful life for years after bad spots begin to show up. The number of bad spots in the Grown Defect List over a specified time as a % of capacity can be an predictor of impending failure, however. Andy Cress