Date: Fri, 15 Oct 1999 11:00:16 -0400 (EDT) From: Andrew Gallatin <gallatin@cs.duke.edu> To: "Kenneth D. Merry" <ken@kdm.org> Cc: scsi@FreeBSD.ORG Subject: Re: FreeBSD 3.2 / Slow SCSI Dell PowerEdge 4300 Message-ID: <14343.16009.738375.608477@grasshopper.cs.duke.edu> In-Reply-To: <19991015125107.A56477@chuggalug.clues.com> References: <Pine.BSF.4.10.9910141552550.15842-100000@atlas.rccn.net> <199910142255.QAA46124@panzer.kdm.org> <19991015125107.A56477@chuggalug.clues.com>
next in thread | previous in thread | raw e-mail | index | archive | help
Geoff Buckingham writes: > On Thu, Oct 14, 1999 at 04:55:45PM -0600, Kenneth D. Merry wrote: > > > > Western Digital drives generally aren't that great. In fact, we have > > disabled tagged queueing for most all Western Digital SCSI drives. > > (including the drives you have, above) > > > > I have been meaning to post on this subject for some time, while in my last > place of employment I bought 8 Dell PowerEdge 2300s each with six drives > Dell supplied Western digitals and I had really poor disk performance. > > I realised tagged queing was disabled for WDE* and removed the quirk from > cam_xpt.c this greatly improved the performance. Much exercising of the disks > also failed to cause any further problems. I'm the guy to blame for this quirk. My drives (shipped in about 60 older Dell Dimension XPS D300 here) have abysmal sequential write performance with tagged queuing enabled. There are two types of identifiers: pass0: <WDIGTL WDE4360-1807A3 1.80> Fixed Direct Access SCSI-2 device pass0: Serial Number WS7010610507 pass0: 40.000MB/s transfers (20.000MHz, offset 8, 16bit) pass1: <WDIGTL ENTERPRISE 1.91> Fixed Direct Access SCSI-2 device pass1: Serial Number WS7011244369 pass1: 40.000MB/s transfers (20.000MHz, offset 8, 16bit) 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? Also, would it be possible to enable/disable tagged queuing from camcontrol? Or to read the quirks from a config file (like Digital UNIX does with its ddr.db file..). Drew ------------------------------------------------------------------------------ Andrew Gallatin, Sr Systems Programmer http://www.cs.duke.edu/~gallatin Duke University Email: gallatin@cs.duke.edu Department of Computer Science Phone: (919) 660-6590 To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-scsi" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?14343.16009.738375.608477>