From owner-freebsd-hardware Wed Feb 24 13:38: 0 1999 Delivered-To: freebsd-hardware@freebsd.org Received: from duke.cs.duke.edu (duke.cs.duke.edu [152.3.140.1]) by hub.freebsd.org (Postfix) with ESMTP id 7499F11EB2 for ; Wed, 24 Feb 1999 13:36:00 -0800 (PST) (envelope-from gallatin@cs.duke.edu) Received: from grasshopper.cs.duke.edu (grasshopper.cs.duke.edu [152.3.145.30]) by duke.cs.duke.edu (8.9.1/8.9.1) with ESMTP id KAA19858; Wed, 24 Feb 1999 10:16:41 -0500 (EST) Received: (from gallatin@localhost) by grasshopper.cs.duke.edu (8.9.2/8.9.1) id KAA26637; Wed, 24 Feb 1999 10:16:31 -0500 (EST) (envelope-from gallatin@cs.duke.edu) From: Andrew Gallatin MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Date: Wed, 24 Feb 1999 10:16:31 -0500 (EST) To: Ruslan Ermilov Cc: "Kenneth D. Merry" , allenc@verinet.com, hardware@freebsd.org Subject: Re: Tagged queueing and write cache on WDE SCSI drives In-Reply-To: <19990224150930.A6284@ucb.crimea.ua> References: <19990223182845.A32766@ucb.crimea.ua> <199902240617.XAA37750@panzer.plutotech.com> <19990224150930.A6284@ucb.crimea.ua> X-Mailer: VM 6.43 under 20.4 "Emerald" XEmacs Lucid Message-ID: <14036.2148.617961.183536@grasshopper.cs.duke.edu> Sender: owner-freebsd-hardware@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org Ruslan Ermilov writes: > The best performance is achieved with WC=ON and TQ=OFF. > > Comments? More tests? > > Is this WD-specific? We have a large number of WD drives which came in donated Intel PII's For all these drives, TQ off, WC on gives the best results. For other vendor's drives (various models of modern Seagate barricuda & cheetah drives), TQ on, WC on gives the best results. Given any choice in the matter, I'd never willingly purchase a WD scsi drive. Even most modern UDMA IDE drives perform far better. ------------------------------------------------------------------------------ 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-hardware" in the body of the message