dplatt@coherent.com (Dave Platt) (12/23/89)
My upgrade-copy of DiskExpress II arrived last night. I installed
it on my Mac II and played with it for a couple of hours.
Impressions:
- It's sophisticated. A lot of thought went into it.
- Its disk-compaction scheme is different than that of DiskExpress.
DiskExpress packs everything together at the beginning of the volume
with the free space at the end. DiskExpress II places frequently-
used files at the beginning of the volume, with "active" files
(used but not changed in size) before "volatile" (used, and changed
in size). Unused files, and those used only occasionally, go at
the end of the volume. The free space goes in the middle.
This seems like a very effective scheme.
- It keeps track of what files you use, accumulates this information over
a period of several days, and uses the information to decide which
files to put where. You can turn this monitoring off on a volume-
by-volume basis; if you do, DiskExpress II won't automatically optimize
the volume, and it'll use some built-in assumptions about file usage
when you optimize manually.
- It does indeed operate in the background. A few minutes after you boot,
it starts up, does a read-verification pass on the volume (checking for
bad blocks), analyzes your usage, and then starts moving files around.
If you start doing some work (typing, clicking, etc.), DiskExpress II
goes idle until you've had your hands off the machine for a while
(10-15 seconds, I think).
- You can do a block-verify or an optimization pass at any time, by
opening up the Control Panel device and clicking a few times.
DiskExpress II puts up a dialog box so you can monitor its progress.
- You can bring up a display of a volume's fragmentation status from
the Control Panel. The display is more sophisticated than that
available in DiskExpress... it categorizes blocks into one of four
categories which are displayed using different patterns or colors.
- DiskExpress II can move System files, applications, INITs, etc. around
without triggering Gatekeeper vetoes.
I've only run into one glitch so far.. it's significant but not really
dangerous, as far as I can tell:
* If DiskExpress II is performing a background optimization, opening up
or closing the Control Panel device appears to disrupt the optimization.
If DEII was optimizing the boot volume, opening up the Control Panel
device causes this optimization to stop. Optimization proceeds with
the next eligible volume. The boot-volume won't be optimized again
unless you reboot, or (I infer) wait until the next day, or
optimize it manually from the Control Panel.
If DEII is optimizing a volume, and you _close_ its Control Panel
device, the optimization is disrupted in a strange way. I've done
this four times. Once, DEII put up a "Grim Reaper" dialog telling
me that a problem had been found in the directory on the volume
being optimized. Twice, DEII aborted the optimization and reported
an error code of -38 (which my crib-DA tells me is "File isn't open").
Once, my Mac II hung, and required a reboot.
In none of these situations did any apparent damage occur to my
disk volume or to the files therein (although only time will tell
whether other problems lurk within).
I've been trying to get through to ALSoft to report this problem, but
their lines are busy... I suspect others have encountered it, as well ;-).
Overall, I'm _very_ impressed. I wish I knew how they're able to do
what they're doing!
--
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USNAIL: Coherent Thought Inc. 3350 West Bayshore #205 Palo Alto CA 94303warner@s3dawn.ARPA (Ken Warner) (12/23/89)
I've tried to run DiskExpress II in automatic optimization mode on a volume where I run ParcPlace Smalltalk-80 V2.3. It *seems* to cause Smalltalk-80 to fail with "Smalltalk unexpectedly quit" followed by a system error. I say *seems* because immediately after I installed DEII, I began to get these errors. After three failures I manually optimized the affected volume and turned DEII off. No more problems and a noticeable performance improvement. I will continue to use DEII manually until I switch to V2.5. Then I'll try it again. Ken Warner
magik@chinet.chi.il.us (Ben Liberman) (12/25/89)
I've been running DE II for 4 days now and have had numerous crashes on what was a fairly stable system. Last month, a pgm. called United 1.04, came across comp.binaries.mac After it crashed a few times, I removed all INITS except DE II, and my mac (SE/30, 6.0.3, 5 meg.) crashed every time I tried to run it. What I'm doing, until they release a bug fix, is remove DE II and reinstall it every few days ONLY to do a manual optimization and then remove it again. I lose the benifit of it's monitoring and customized optimization. I still prefer it to the original DiskExpress which required booting from a seperate volume. ah....life...:-( -- ------------ ------------ ---------------------- Ben Liberman USENET magik@chinet.chi.il.us GEnie,Delphi MAGIK
carmi@mars.jpl.nasa.gov (Aviram Carmi) (12/27/89)
In article <1989Dec24.200013.3435@chinet.chi.il.us> magik@chinet.chi.il.us (Ben Liberman) writes: >I've been running DE II for 4 days now and have had numerous crashes on what >was a fairly stable system.... > >What I'm doing, until they release a bug fix, is remove DE II and reinstall it >every few days ONLY to do a manual optimization and then remove it again. I >lose the benifit of it's monitoring and customized optimization. I still prefer >it to the original DiskExpress which required booting from a seperate volume. > >ah....life...:-( I have also experianced numerous crashes, even with the machine idling. i.e. no programs running or program running but not doing a thing for couple of minutes and than suddenly the machine would crash. My solution was to use the "off" radio button, uncheck auto monitoring, and do manual optimization by checking the "on" button and optimizing. Avi Carmi (carmi@mars.jpl.nasa.gov)
magik@chinet.chi.il.us (Ben Liberman) (12/28/89)
I talked to AlSoft today (713-353-1510 for tech support) and they are sending me Release 2.03 (I have 2.00). As usuall, reports to the interested - summary to the net if demand warrants -- ------------ ------------ ---------------------- Ben Liberman USENET magik@chinet.chi.il.us GEnie,Delphi MAGIK
cca@pur-phy (Charles C. Allen) (12/30/89)
Is it possible to run Disk Express II in the same way as the original Disk Express? I would like to know if DE II can be used as an application that I fire up once a month. I specifically don't want anything to be installed as an INIT, DA, etc. The upgrade info seems unclear about this. Charles Allen cca@newton.physics.purdue.edu
carmi@mars.jpl.nasa.gov (Aviram Carmi) (01/01/90)
In article <2948@pur-phy> cca@pur-phy (Charles C. Allen) writes: >Is it possible to run Disk Express II in the same way as the original >Disk Express? I would like to know if DE II can be used as an >application that I fire up once a month. I specifically don't want >anything to be installed as an INIT, DA, etc. The upgrade info seems >unclear about this. > >Charles Allen cca@newton.physics.purdue.edu Disk Express II is an init/cdev combination. It can be configured to automatically monitor your drives for file usage and to automatically optimize in the background while either finder or multifinder is running. It can also be configured to only monitor your usage without automatic optimization, which can be done manually through the control panel. Or you can also disable the monitoring and when you optimize manually, Disk Express will use a default algorithm to optimize the disk. They do have a problem automatically optimizing under system 6.0.2 (which is what I am using), as soon as it tries to optimize in the background it crashes. I called tech support and they are sending me version 2.03 which should solve this problem (the problem does not exist under 6.0.3, I did not ask about 6.0.4). Meanwhile I was told to disable automatic optimization but to enable monitoring, and optimize manually every few days, which seems to work fine. So you can use it in the monitoring/manual optimizing mode and manually optimize once a month. Hope this clarifies things a bit. Avi Carmi (carmi@mars.jpl.nasa.gov)
dplatt@coherent.com (Dave Platt) (01/03/90)
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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USNAIL: Coherent Thought Inc. 3350 West Bayshore #205 Palo Alto CA 94303bmug@garnet.berkeley.edu (BMUG) (01/04/90)
In article <43490@improper.coherent.com> dplatt@coherent.com (Dave Platt) writes: >(lots of observations about DiskExpress II behavior) > Has anyone yet used DiskExpress II on an AppleShare file server? Seems to me that a server would tend to develop more fragmentation than a normal user's hard disk, particularly if something like a database is being accessed and augmented regularly. And because a network is only as fast as its slowest component, it's reasonable to think that you want your server disk to be operating as efficiently and quickly as possible. John Heckendorn /\ BMUG ARPA: bmug@garnet.berkeley.EDU A__A 1442A Walnut St., #62 BITNET: bmug@ucbgarne |()| Berkeley, CA 94709 Phone: (415) 549-2684 | |