From owner-freebsd-scsi Thu Jul 5 17: 4:41 2001 Delivered-To: freebsd-scsi@freebsd.org Received: from mailhub.fokus.gmd.de (mailhub.fokus.gmd.de [193.174.154.14]) by hub.freebsd.org (Postfix) with ESMTP id 9AC7937B403 for ; Thu, 5 Jul 2001 17:04:37 -0700 (PDT) (envelope-from schilling@fokus.gmd.de) Received: from fokus.gmd.de (sherwood [193.175.133.102]) by mailhub.fokus.gmd.de (8.8.8/8.8.8) with ESMTP id CAA08888; Fri, 6 Jul 2001 02:04:28 +0200 (MET DST) Received: (from jes@localhost) by fokus.gmd.de (8.8.8+Sun/8.8.8) id CAA04785; Fri, 6 Jul 2001 02:03:53 +0200 (MET DST) Date: Fri, 6 Jul 2001 02:03:53 +0200 (MET DST) From: Joerg Schilling Message-Id: <200107060003.CAA04785@fokus.gmd.de> To: ken@kdm.org, schilling@fokus.gmd.de Cc: freebsd-scsi@freebsd.org, gibbs@scsiguy.com, mckay@thehub.com.au Subject: Re: Problems reading burned CDs Sender: owner-freebsd-scsi@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.org >From ken@panzer.kdm.org Fri Jul 6 00:45:37 2001 >> >> >Sending a Bus Device Reset message to a target when it doesn't respond >> >in the expected amount of time is a bug? Perhaps the driver could try >> >an abort message first, but the behavior is not completely unreasonable. >> >Your other complaints seem to be in regard to a "bus reset", which never >> >occurred in this situation. >> >> OK, if it is no bus device reset, it should be OK. >Eh? It is a bus device reset... I believe you are talking about a target reset which does not reset the whole bus but a specific target. >> However, 5 seconds is a too short timeout. >For what? The 5 second timeout is for a generic SCSI command facility, >not for any particular command. 5 seconds is plenty of time for some >commands, and way too short for others. A user savvy enough to compose >his own CDBs should also be knowledgeable enough to specify a suitable >timeout. Believe that _any_ SCSI device I know will take much longer if there is some problem to read the media. For a hard disk you should wait at least 20 seconds for error recovery (this means read retries _and_ eventually error correction). If a CD-ROM uses error correction, you should give it ~ 100 seconds. If you don't follow these rules, you will end up believing that there are completely _unreadable_ blocks where the media is only _very hard_ to read. Jörg EMail:joerg@schily.isdn.cs.tu-berlin.de (home) Jörg Schilling D-13353 Berlin js@cs.tu-berlin.de (uni) If you don't have iso-8859-1 schilling@fokus.gmd.de (work) chars I am J"org Schilling URL: http://www.fokus.gmd.de/usr/schilling ftp://ftp.fokus.gmd.de/pub/unix To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-scsi" in the body of the message