From owner-freebsd-bugs Fri May 26 10:17:33 1995 Return-Path: bugs-owner Received: (from majordom@localhost) by freefall.cdrom.com (8.6.10/8.6.6) id KAA00653 for bugs-outgoing; Fri, 26 May 1995 10:17:33 -0700 Received: from gndrsh.aac.dev.com (gndrsh.aac.dev.com [198.145.92.241]) by freefall.cdrom.com (8.6.10/8.6.6) with ESMTP id KAA00646 for ; Fri, 26 May 1995 10:17:20 -0700 Received: (from rgrimes@localhost) by gndrsh.aac.dev.com (8.6.11/8.6.9) id KAA02456; Fri, 26 May 1995 10:16:54 -0700 From: "Rodney W. Grimes" Message-Id: <199505261716.KAA02456@gndrsh.aac.dev.com> Subject: Re: MAJOR problem with FreeBSD-2.0-RELEASE To: dufault@hda.com (Peter Dufault) Date: Fri, 26 May 1995 10:16:54 -0700 (PDT) Cc: davidg@Root.COM, hsu@cs.hut.fi, freebsd-bugs@freefall.cdrom.com In-Reply-To: <199505261221.IAA05683@hda.com> from "Peter Dufault" at May 26, 95 08:21:33 am X-Mailer: ELM [version 2.4 PL24] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Content-Length: 1346 Sender: bugs-owner@FreeBSD.org Precedence: bulk > > David Greenman writes: > > > > >all accesses to the disk which first generated an error fail. Everything > > >around the disks, including cables have been changed several times, so it > > >is either the disks or the software. > > > > Probably both. One of the drives is hanging the SCSI bus, and FreeBSD > > doesn't cope with it correctly. I've seen this happen myself... > > Properly resetting the SCSI bus, the host adapter, renegotiating > sync transfers, waiting for all devices to come ready again and > getting their "bus device reset occurred" message, reaping all > outstanding I/O transactions, and then retrying those outstanding > transactions is an effort that includes modifying all the host > adapter drivers (and looking for a common interface to pull up out of > them) and so will be a tough job to adequately test. It should > also be done in conjunction with better I/O transaction scheduling > to cleanly support tag queuing. This is a 2.1 adventure. This is a 2.2 adventure, we are not going to do that kind of massive work in any part of the system until after 2.1 ships. We simply can not afford the risk factor at this time. This is of cource, IMHO. -- Rod Grimes rgrimes@gndrsh.aac.dev.com Accurate Automation Company Custom computers for FreeBSD