🚀 go-pugleaf

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