From owner-freebsd-scsi Fri Oct 15 13:17:55 1999 Delivered-To: freebsd-scsi@freebsd.org Received: from panzer.kdm.org (panzer.kdm.org [216.160.178.169]) by hub.freebsd.org (Postfix) with ESMTP id 8816B14BC8 for ; Fri, 15 Oct 1999 13:17:49 -0700 (PDT) (envelope-from ken@panzer.kdm.org) Received: (from ken@localhost) by panzer.kdm.org (8.9.3/8.9.1) id OAA51280; Fri, 15 Oct 1999 14:17:41 -0600 (MDT) (envelope-from ken) Message-Id: <199910152017.OAA51280@panzer.kdm.org> Subject: Re: FreeBSD 3.2 / Slow SCSI Dell PowerEdge 4300 In-Reply-To: <19991015201103.B56536@chuggalug.clues.com> from Geoff Buckingham at "Oct 15, 1999 08:11:03 pm" To: geoffb@chuggalug.clues.com (Geoff Buckingham) Date: Fri, 15 Oct 1999 14:17:41 -0600 (MDT) Cc: mjacob@feral.com (Matthew Jacob), gallatin@cs.duke.edu (Andrew Gallatin), scsi@FreeBSD.ORG From: "Kenneth D. Merry" X-Mailer: ELM [version 2.4ME+ PL54 (25)] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-freebsd-scsi@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org Geoff Buckingham wrote... > > On Fri, 15 Oct 1999, Andrew Gallatin wrote: > > > >From the reports I've seen, it looks like Western Digital got their > > > act together and their Ultra2 drives are OK. Could we make the quirk > > > entry enable tagged queuing for Ultra2 WDE drives & disable it for > > > non-ultra2 drives? > > I just got this from a former colleage, details of the drives we had: > > da4 at ahc0 bus 0 target 4 lun 0 > da4: Fixed Direct Access SCSI-2 device > da4: 80.000MB/s transfers (40.000MHz, offset 31, 16bit) > da4: 8687MB (17793001 512 byte sectors: 255H 63S/T 1107C) > > In my opinion these do not require the quirk. > > (based on bonnie results for individual disks with WCE as shipped (off i think) > you get better sequential performance and more importantly for most of us > better seeking) I'd like to see some hard numbers for these before I change the quirk. (i.e. bonnie numbers at 1, 2, 4, 8, 16, 32, and 64 tags, with and without write caching) camcontrol can be used to change the tags and enable/disable write caching on the fly. If anyone wants to do this, see PR kern/10398 for an example of what sort of tests to run. In any case, it'll be a little tricky to do the quirk so it'll still match the non-Ultra2 WD drives that are apparantly still broken. (A "positive" quirk entry followed by the current quirk entry would probably do the trick, since the first matching quirk entry in the table is used.) Ken -- Kenneth Merry ken@kdm.org To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-scsi" in the body of the message