From mboxrd@z Thu Jan 1 00:00:00 1970 From: Doug Ledford Subject: Re: [PATCH + RFC] Beginning of some updates to scsi mid layer Date: Sat, 29 Jun 2002 06:05:09 -0400 Sender: linux-scsi-owner@vger.kernel.org Message-ID: <20020629060509.A23827@redhat.com> References: <10206281819.ZM1024786@classic.engr.sgi.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: ; from mjacob@feral.com on Fri, Jun 28, 2002 at 07:04:28PM -0700 List-Id: linux-scsi@vger.kernel.org To: Matthew Jacob Cc: Jeremy Higdon , Martin Peschke3 , Pete Zaitcev , linux-scsi@vger.kernel.org On Fri, Jun 28, 2002 at 07:04:28PM -0700, Matthew Jacob wrote: > > FWIW, Bob Snively (on T10 commitee) has always claimed that the correct > response to QUEUE FULL is immediate command resubmission (i.e., *don't* wait > for a command to complete (the QFULL may have resulted from commands being > processed for *another* initiator), and *don't* a period of time for things to > 'get better'). > > I'm not sure agree with this 100%, but he might have a point. No, absolutely not! Faster drivers are capable of restarting commands on the bus so fast that in this scenario they can flood the bus with selection, command, queue full sequences and not allow *any* commands to complete because the bus is always tied up (this was, in fact, one of the reasons that I had to put the queue handling code in the aic7xxx driver when I did). -- Doug Ledford 919-754-3700 x44233 Red Hat, Inc. 1801 Varsity Dr. Raleigh, NC 27606