From owner-freebsd-scsi  Mon Aug 26 23:59:37 1996
Return-Path: owner-freebsd-scsi
Received: (from root@localhost)
          by freefall.freebsd.org (8.7.5/8.7.3) id XAA18456
          for freebsd-scsi-outgoing; Mon, 26 Aug 1996 23:59:37 -0700 (PDT)
Received: from odie.physik2.uni-rostock.de (odie.physik2.uni-rostock.de [139.30.40.28])
          by freefall.freebsd.org (8.7.5/8.7.3) with ESMTP id XAA18435;
          Mon, 26 Aug 1996 23:59:33 -0700 (PDT)
Received: (from lkoeller@localhost)
          by odie.physik2.uni-rostock.de (8.7.5/8.7.3) id IAA20672;
          Tue, 27 Aug 1996 08:59:25 +0200 (MET DST)
Date: Tue, 27 Aug 1996 08:59:25 +0200 (MET DST)
From: Lars Koeller <Lars_Koeller@odie.physik2.uni-rostock.de>
Message-Id: <199608270659.IAA20672@odie.physik2.uni-rostock.de>
X-Face: nLQGe[[K51[{{[C\,BiQm[7]u1<r*biUsbPfYvu!Ee"NMw+TUPr`[d`9M2Z@?K79e,e0hGO
 fWn;9\[H~N.vTWNY>m{N>_\%nLBo4t@)CoZ}hK[W7DwX&V=}Wf#Qb,j:Jpj[(12r=b~:dYmh]fDf\,
 ]_frt6e<dI[U8(?zxR|UKs(CXNU>M<fA||Pim|ljOlWpT$FEK#{iPI$ZdS}V6cx}nyDe"<hSP#6<y3
 3$gO:t{F7o,tYE=4a$ZTF+%7w=UFjMsWObjlS`z9^8$*rOb<rlN{lusO'Ys
To: se@ZPR.Uni-Koeln.DE, wjw@IAEhv.nl (Willem Jan  Withagen)
Subject: Re: SCSI disks
In-Reply-To: Mail from 'Stefan Esser <se@ZPR.Uni-Koeln.DE>'
      dated: Mon, 26 Aug 1996 21:09:38 +0200 (MET DST)
Cc: hardware@freebsd.org, scsi@freebsd.org, admin@IAEhv.nl
Sender: owner-freebsd-scsi@freebsd.org
X-Loop: FreeBSD.org
Precedence: bulk


   Hi!

   Stefan Esser writes:
 
> Willem Jan Withagen writes:
>  > 
>  > Hi,
>  > 
>  > Until recently we as an ISP were using Micropolis disk with pleasure.
>  > But since several 4.3Gb started crashing, we've changed our view.
>  > 
>  > So I'm now looking for new disks. I've got 2 offerings:
>  > 	Seagate Barracuda 4.3 GB
>  > 	Quantum XP34300S
>  > The need to run on FreeBSD 2.0.5 and up. 
>  > Long agood I tested the quantum with an NCR 53810 and an Adaptec 1542B 
>  > and in both case it did not seem to work. Now things might have changed, but
> 
> Hmmm, that's surprising, since my current development system uses
> a Quantum Atlas (though its the XP32150S, the 2GB version). This 
> drive worked with the NCR driver of Spring 1995 at least, when I 
> first tested it.
> 
> I'm quite sure that the Adaptec 1542 supported it as well, since
> it is hard to find a device that doesn't work on the Adpatec, and
> the Atlas is really well designed (IMHO).
> 
> The Quantum Grand-Prix (XP34301S) is a different beast. It has got 
> bad press because of many failed (or DOA) drives, and it is noisy 
> and significantly slower than the Atlas, though both are 7200RPM
> drives.
> 
> You may also want to have a look at the IBM DHFS series, which is 
> also very fast and AFAIK reliable.
> 
> Can't comment on recent Seagate drives.
> 
> Regards, STefan


      Perhaps  it's  the same  phenomena  I have  with the  Quantum and the
   Adaptec 1742 EISA SCSI controller. Every time the  disc reads out of the
   cache, the response is so quick  that a lot  of controllers aren't ready
   to receive the first bytes.  As  a matter of  fact the whole SCSI-bus is
   locked! The  solution is to edit the   modepage of the  Quantum Atlas so
   that   the disc inserts  a   delay of 15  micro seconds  when a block is
   transfered out of the cache.

      If you need any information how to do this, don't hesitate to contact
   me again.

   Regards

   Lars

-- 
________________________________________________________________________
Lars Köller                  Phone:  +49 381/498-1665, Fax: -1667
University of Rostock        E-Mail: 
Department of Physics          Lars_Koeller@odie.physik2.Uni-Rostock.DE
Universitätsplatz 3          Anonymous ftp:
D-18051 Rostock (Germany)      ftp://odie.physik2.uni-rostock.de/pub