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Faster BACKUP? Larger Directories?

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The Question is:

I have an application that due to some design limitations has produced a
directory with 297,000 files in it. I now want to move this directory onto a
new machine running 7.2-1 on a volume using OSD5 but when I tried restoring
it, it took a little longer t
han expected. I killed it after almost 3 days. The souce volume is only
about 45GB and all the files have unique names. The target disk is made up
of 5 36GB drives in a RAID5 set. I have had to partition the disk as the
application has some specfic requir
ements on volume labels and I am putting 3 disks worth of data onto the one
big array (In separate directories)
The question is, how can I get the restore to go faster. The restore created
the directory at the same size as the source so I shouldn't have been a
problem with the directory file expanding and needing to be move for more
contiguous space. It gets slower
 and slower as the directory fills up. The source volume took 2 years for
the application to fill up.
Ian Mackay
System and Network manager
Publishing and Broadcasting Limited

The Answer is :

  You do not mention what command(s) were used for the transfer.
  The OpenVMS Wizard would suggest using BACKUP/IMAGE of the entire disk
  for the transfer, with the appropriate system and process quotas enabled.
  Either disk-to-disk, or disk-tape-disk, depending on the currency of any
  available BACKUP.   (For details on the recommended quotas, please see
  the OpenVMS System Management documentation.  Divergence from the quotas
  recommended for the BACKUP username can lead to performance problems.)
  The OpenVMS Wizard would use an OpenVMS V7.2 or later OpenVMS version,
  or an OpenVMS V7.2 or later bootable environment for the transfer.
  You will also want to consider the disk cluster size settings.  If you
  wish to override the default cluster factor -- the default cluster size
  is compatible with earlier OpenVMS releases, leading to large cluster
  factors on larger disks -- then you must initialize the target volume
  (via INITIALIZE) and also select the /INITIALIZE qualifier on BACKUP.
  (A disk cluster factor of one block is permitted on disk volumes of
  capacities up to circa 137 GB, on OpenVMS V7.2 and later.)
  There is no need to specify ODS-5 as part of the transfer, as switching
  an ODS-2 volume to ODS-5 (entirely in place) is both quick and trivial.
  (ODS-2 also has the same performance-related changes for large directories
  and cluster size as are available for ODS-5.)

answer written or last revised on ( 7-FEB-2000 )

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