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STACKER NOTE                          Stac Electronics Technical Note

Subject: Third party defragmentation programs and STACKER 2.0 and 1.x

Tech001 - 2/20/92
Page 1 of 1 
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Writing to disk can cause file fragmentation over time.  Third party 
defragmentation programs such as Norton Speedisk, PCtools Compress, and 
VOPT can remedy this condition on uncompressed drives, but should NOT be 
run on STACKER drives.  

Q: Why can't I run third party Defragmenters on a STACKER drive?
A: STACKER's special method of storing compressed data cannot be 
   interpreted by these programs.  If run on a STACKER drive, they can 
   actually increase fragmentation.  It is O.K. to run third party 
   defragmenters on the noncompressed drive.

Q: How do I defragment a STACKER drive?
A: Stacker version 2.0 includes a defragmentation utility called SDEFRAG.  It 
   is specifically designed to defragment STACKER drives.  It will not 
   defragment a noncompressed drive.  To defragment a STACKER version 1.x 
   drive, it is necessary to back up the data on the drive, delete the data 
   on the drive, then restore from the backup.  A recommended alternative is 
   to upgrade to STACKER 2.0 and use SDEFRAG .

Q: What if I accidently ran a third party defragmenter on a STACKER drive?
A: Your data remains safe, however, the fragmentation may have been 
   increased.  Run SCHECK /f to correct any errors on the drive.  Then run 
   SDEFRAG to defragment the drive.




















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Copyright * 1992 STAC ELECTRONICS



