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Availability Manager and Swapfiles?

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The Question is:

This is under 7.3, yes I have the real released version up already. Using
Avail 7.3, from the KIT, It reports that all of my 7.3 Systems are missing
their Swapfiles. Am I doing something wrong or is this a feature ? :)

The Answer is :

  If your systems have valid and correctly configured swapfiles, then
  this would appear to be a bug in the Availability Manager.  Please
  contact the Compaq Customer Support Center; expect to be asked details
  of the current swapfile configuration.
  If your systems have no swapfiles, then the output is appropriate.
  This particular configuration would have been made by explicit choice
  of the System Manager.   See SHOW MEMORY/FILE/FULL for details:
              System Memory Resources on 17-APR-2001 10:40:00.63
    Free Blocks                   9984    Reservable Blocks             9984
    Total Size (blocks)          49920    Paging File Number               1
    Swap Usage (processes)          39    Paging Usage (processes)         0
  This file is used exclusively for swapping.
    Free Blocks                3345536    Reservable Blocks          3089664
    Total Size (blocks)        3999872    Paging File Number               3
    Swap Usage (processes)           0    Paging Usage (processes)       102
  This file can be used for either paging or swapping.
  A file that is installed as a swapfile is "used exclusively for
  swapping", while a pagefile "can be used for either paging or
  swapping".  The difference involves the organization of the data
  structures within the two types of files.  The data structures within
  the pagefile are optimized for paging, but can provide for swapping
  activity.  The structures within the swapfile target swapping, and
  are ill-suited for paging.
  In antiquity, swapping was considered evil and slow and was to be
  avoided.  Today, swapping processes out is far faster and is often
  appropriate for efficient use of physical memory resources.  In the
  above system, there are a significant number of processes swapped out,
  most of which have been idle for extended periods.  That these processes
  are swapped out leaves more memory for active processes, thus improving
  overall system performance.  (Had this system been configured without a
  swapfile, those processes would have been swapped into the pagefile.)
  The OpenVMS Wizard recommends that a system manager track typical paging
  and swapping activity, and configure page and swap files appropriately
  (makes note to self to boost the swapfile on the above system by 50,000
  blocks ;-)  The OpenVMS Wizard would also encourage system managers to
  be aware of the real, dollar cost of disk space when configuring page
  and swap files.  US$10 worth of disk space is a very small price to
  prevent system problems resulting from insufficient (or inaccessable)
  pagefile (or swapfile) storage.

answer written or last revised on ( 8-MAY-2001 )

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