*BSD News Article 58167


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From: drew@qualcomm.com (Drew Eckhardt)
Newsgroups: comp.unix.bsd.freebsd.misc,comp.periphs.scsi
Subject: Re: SCSI-2 Bus Hangs
Date: 26 Dec 1995 15:21:50 -0700
Organization: QUALCOMM, Incorporated; San Diego, CA, USA
Lines: 17
Message-ID: <4bpshu$asf@qualcomm.com>
References: <4bju5p$ihj@wilma.widomaker.com> <4bnidn$lej@almond.elite.net>
NNTP-Posting-Host: redcloud.qualcomm.com
Keywords: SCSI-2 Lockup
Xref: euryale.cc.adfa.oz.au comp.unix.bsd.freebsd.misc:11472 comp.periphs.scsi:43840

In article <4bnidn$lej@almond.elite.net>, Nate Lawson <nate@elite.net> wrote:
>Also, the NCR chipset is absolute junk.

NCR 53c8xx family chips aren't affected as much as recent Adaptec products 
by sub-optimal cabling, handle error-free I/O operations with no host CPU 
intervention, have minimal per-SCSI command overhead, no arbitrary limits on 
the number of scatter/gather segments, and end up being quite fast.  Under 
FreeBSD, a 486-66 with modern 7200RPM drive can sustain over 6500K/sec 
through a FFS filesystem. Aggregate transfer rates in excess of 20M/sec 
through the filesystem have been sustained with multiple NCR chips and 
spindles.  The NCR design also requires almost no off-chip support hardware, 
AND results in a very cost-effective (I've seen '810 boards for $53, and 
'825 boards for $110) solution.  In summary, I'd say the hardware is excellent.

-- 
Four boxes : soap, ballot, jury, ammo.  | Work: drew@Qualcomm.COM       
Use in that order.                      | Play: drew@PoohSticks.ORG