From owner-freebsd-current Sun Dec 9 23:49:38 2001 Delivered-To: freebsd-current@freebsd.org Received: from rwcrmhc53.attbi.com (rwcrmhc53.attbi.com [204.127.198.39]) by hub.freebsd.org (Postfix) with ESMTP id 53F4B37B405 for ; Sun, 9 Dec 2001 23:49:31 -0800 (PST) Received: from peter3.wemm.org ([12.232.27.13]) by rwcrmhc53.attbi.com (InterMail vM.4.01.03.27 201-229-121-127-20010626) with ESMTP id <20011210074931.WKCQ24045.rwcrmhc53.attbi.com@peter3.wemm.org> for ; Mon, 10 Dec 2001 07:49:31 +0000 Received: from overcee.netplex.com.au (overcee.wemm.org [10.0.0.3]) by peter3.wemm.org (8.11.0/8.11.0) with ESMTP id fBA7nVs33021 for ; Sun, 9 Dec 2001 23:49:31 -0800 (PST) (envelope-from peter@wemm.org) Received: from wemm.org (localhost [127.0.0.1]) by overcee.netplex.com.au (Postfix) with ESMTP id DC9DC38CC; Sun, 9 Dec 2001 23:49:30 -0800 (PST) (envelope-from peter@wemm.org) X-Mailer: exmh version 2.5 07/13/2001 with nmh-1.0.4 To: Matthew Dillon Cc: freebsd-current@FreeBSD.ORG Subject: IBM DTLA drives (was: Re: "Dangerously dedicated" yet again (was: cvs commit: src/sys/kern subr_diskmbr.c) ) In-Reply-To: <200112100707.fBA77rJ44369@apollo.backplane.com> Date: Sun, 09 Dec 2001 23:49:30 -0800 From: Peter Wemm Message-Id: <20011210074930.DC9DC38CC@overcee.netplex.com.au> Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG Matthew Dillon wrote: > :> etc... So apparently my warning about these drives in 'man tuning' is > :> still appropriate :-) > :> > :> -Matt > :> > :> :> > IBM DTLA drives are known to rotate fast enough near the spindle > :> :> > that the sustained write speed exceeds the ability of the controller > :> :> > electronics to keep up, and results in crap being written to disk. > : > : > :I would adssume it actually the tracks FURTHEREST from the spindle.. > > This is the first I've heard of the alleged controller electronics > performance problem. My understanding is that the failures are due > to manufacturing problems, but people have apparently experienced > software lockups as well. > > What is not in doubt is that there have been some severe problems with > this model. Yes there are two problems. The physical failure problem seems to be mostly restricted to the 75GXP. However the electronics/bandwidth/ density/whatever-it-is problem is uniform across the entire DTLA line. We stopped using 75GXP's at work a while back, but we still regularly suffer from the electronics/bandwidth/whatever-it-is problem on 30G DTLA drives on a daily basis. Cheers, -Peter -- Peter Wemm - peter@FreeBSD.org; peter@yahoo-inc.com; peter@netplex.com.au "All of this is for nothing if we don't go to the stars" - JMS/B5 To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message