Path: utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!sun-barr!newstop!sun!coherent!dplatt
From: dplatt@coherent.com (Dave Platt)
Newsgroups: comp.sys.mac
Subject: Re: DiskExpress II - first impressions
Message-ID: <43490@improper.coherent.com>
Date: 3 Jan 90 06:25:35 GMT
References: <42808@improper.coherent.com> <1989Dec24.200013.3435@chinet.chi.il.us> <2450@jato.Jpl.Nasa.Gov> <2948@pur-phy> <2476@jato.Jpl.Nasa.Gov>
Reply-To: dplatt@coherent.com (Dave Platt)
Distribution: comp
Organization: Coherent Thought Inc., Palo Alto CA
Lines: 58

I phoned ALSoft last Friday, and reported the two problems I had seen
during background optimizations.

1) Opening the Control Panel, while background optimization is taking
   place on the boot volume, causes that optimization to stop, and
   analysis and optimization of the next volume to begin.  Optimization
   of the boot volume starts up again later.

   Response from ALSoft: "That's not a problem."  He didn't say why.

   After observing DE II somewhat further, I infer that it will abort
   its optimization process if you do anything which updates the volume
   being optimized... presumably because any such change invalidates the
   INIT's analysis data.  I believe that opening the Control Panel DA
   causes some change to the System file, and triggers this
   invalidation-check. Fair enough.

2) Closing the DiskExpress II Control Panel, while background
   optimization is taking place on a non-boot volume, causes the
   optimization to abort somewhat messily a few seconds later, with one
   of a number of messages (directory problems, filesystem errors, or a
   system hang).  No loss of data occurred (apparently).

   Response from ALSoft: "Hmm.  That _is_ a problem!  What's your street
   address.  OK, got it... what's your serial number?  OK, I'll send you
   version 2.03".

Version 2.03 arrived today via UPS Blue Label (second-day air).  I
installed and tested it.  Behavior [1] still exists;  I can live with
it.  Behavior [2] is gone... opening and closing the Control Panel
device while a non-boot volume is being optimized has no adverse effect
on the optimization.

I'm impressed, and happy!  DiskExpress II does a very effective job of
optimizing an HFS volume... particularly if you leave the "monitor"
feature turned on, so that it can keep track of which files you're
actually using.  I haven't observed any adverse effect from its
monitoring feature.

Using DiskExpress II is another reason to leave your Mac on overnight.
It does its daily optimization when you boot, _or_ at midnight.  If you
leave your Mac up and running when you go home, you'll come in every
morning to a freshly-optimized disk.

... and, if you have an Apple/Quantum drive with sticky arm-lubricant,
DiskExpress II will probably keep it limbered up during the nightly
workout.  You might be less likely to encounter the dreaded "new-ROM-
decides-to-exercise-the-arm-with-a-terrible-buzzing-and-a-serious-
performance-decrease-while-you-are-trying-to-get-your-term-paper-
printed-for-the-final-time" syndrome.



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