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Date: Thu, 21 Aug 1997 04:33:08 -0500 (CDT)
From: "Daniel M. Eischen" <deischen@iworks.InterWorks.org>
To: andreas@wup.de, freebsd-hardware@FreeBSD.ORG, syssgm@dtir.qld.gov.au
Subject: Re: Quiet SCSI disk?
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> [about the 4GB DCAS 34330W]
>
> >Do you know how many tags it uses (tagged command queuing) ?
> >It was a bit disappointing for me, that the IBM DORS 32160 2.1GB
> >only offers 3 and the the famous QUEUE_FULL condistion ...
>
> I run mine off a Diamond FirePort 40 (uses the 53c875J chip).  When I run
> ncrcontrol, it tells me it is using 4 tags.  I don't know if I can use
> more.  I remember reading somewhere that Stefan thinks 4 is a good number.
> I can't remember his reasoning, or where I read it. :-/

My IBM 32160:

sd0: <IBM DORS-32160W   !# WA3E> type 0 fixed SCSI 2
sd0: Direct-Access 2063MB (4226725 512 byte sectors)

can do at least 16 tags.  I've tested it under Linux with 16
tags and use the default 8 tags under FreeBSD (both with aic7xxx
drivers).

Dan Eischen
deischen@iworks.InterWorks.org