From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mark Lord Subject: Re: [PATCH] scsi_lib.c: continue after MEDIUM_ERROR Date: Tue, 30 Jan 2007 20:41:42 -0500 Message-ID: <45BFF3D6.9050605@rtr.ca> References: <200701301947.08478.liml@rtr.ca> <1170206199.10890.13.camel@mulgrave.il.steeleye.com> <311601c90701301725n53d25a74g652b7ca3bfc64c56@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from rtr.ca ([64.26.128.89]:2462 "EHLO mail.rtr.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932310AbXAaBlo (ORCPT ); Tue, 30 Jan 2007 20:41:44 -0500 In-Reply-To: <311601c90701301725n53d25a74g652b7ca3bfc64c56@mail.gmail.com> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: "Eric D. Mudama" Cc: James Bottomley , linux-kernel@vger.kernel.org, IDE/ATA development list , linux-scsi Eric D. Mudama wrote: > > Actually, it's possibly worse, since each failure in libata will > generate 3-4 retries. With existing ATA error recovery in the drives, > that's about 3 seconds per retry on average, or 12 seconds per failure. > Multiply that by the number of blocks past the error to complete the > request.. It really beats the alternative of a forced reboot due to, say, superblock I/O failing because it happened to get merged with an unrelated I/O which then failed.. Etc.. Definitely an improvement. The number of retries is an entirely separate issue. If we really care about it, then we should fix SD_MAX_RETRIES. The current value of 5 is *way* too high. It should be zero or one. Cheers