Path: utzoo!utgpu!watmath!iuvax!mailrus!ames!coherent!dplatt
From: dplatt@coherent.com (Dave Platt)
Newsgroups: comp.sys.mac.hardware
Subject: Re: Syquest-based drives?
Message-ID: <38622@improper.coherent.com>
Date: 10 Nov 89 20:22:18 GMT
References: <10433@venera.isi.edu> <19235@pasteur.Berkeley.EDU> <1301@lakesys.lakesys.com>
Reply-To: dplatt@improper.UUCP (Dave Platt)
Distribution: na
Organization: Coherent Thought Inc., Palo Alto CA
Lines: 56

In article <1301@lakesys.lakesys.com> macak@lakesys.UUCP (James Macak) writes:

>A couple of additions I'd make: the Ehman-written docs are apparently for
>their non-removable hard drives, as is their utilities disk.  (Before I
>realized this I had tried to install SCSI drivers from the Ehman disk with
>very poor results.)
>
>The other docs I received were from Software Architects, as was the other disk
>of utilities.  Theirs is the SCSI installer to use, in my experience. 
>
>Ehman did include an insert that claims they are working on their own docs for
>the removable drive.

Hmmm.  Have you tested other installers, with other drivers?

The reason I ask, is that I tested out a version of the Software
Architects installer/driver a year or so ago, during the great "System
6.0 breaks third-party disk drivers" debacle.  I was having some trouble
with the driver for my Rodime-based hard disk;  the vendor from whom I
had purchased the drive provided me with a loaner-copy of the Software
Architects driver.

I liked the user-interface of the installer... it's quite flexible and
effective.  The disk-partitioning feature worked as advertised.
However, after reformatting and restoring my files, I was struck by how
SLOW the drive had become.  Most operations seemed to require almost
twice as long as before, and the drive seemed to spend more time
chattering.

I'm not certain why the slowdown occurred.  My primary suspicion is that
the Software Architects driver was doing relatively small data
transfers... perhaps only one block at a time... and wasn't keeping up
with the disk.  It's also possible that the driver was using handshake
transfers rather than blind transfers, and wasn't able to keep up with
the disk at the 1:1 interleave suggested by the installer/formatter.

A few weeks later, I received a 6.0-compatible installer directly from
Rodime, and tried it out.  It wasn't quite as fast as the original
(OEM-vendor-specific) driver, but was _much_ faster than the Software
Architects driver... so I've been using it ever since.

I don't know whether the poor performance of the SA driver was specific
to Rodime drives, whether it would appear on a Syquest-based drive, or
whether the drivers have been updated or rewritten for better
performance (I wouldn't be surprised... it has been over a year).

I'd be very interested to see the results of a read/write/seek
comparison (SCSI Evaluator, for example) between different Syquest-based
drives, using different manufacturers' drivers.  Has anybody run this
sort of comparison?

-- 
Dave Platt                                             VOICE: (415) 493-8805
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