William,

  >EXPIRE INVENTORY command!
  >What does it do, and how often do I have to execute this command.?
  >Will it reduce the size of my database?
[Answered already by others ...]

  >How long does it take to run on  AIX 4.1?

When your system is small - not very long at all, but later, this may be
useful ...

On AIX 4.1.5/ADSM server 2.1.5.12/RS6000-R24 with DB on 7137-RAID Array,
the best I've seen is 24 files/second expired. We expire between 800,000
and 1,000,000 files each week and the elapsed time for the whole operation
averages between 10 and 14 hours. In our experience this is best achieved
on a system which isn't doing much else - otherwise overall performance
degrades all round - so we run this weekly. Our DB is currently 22GB.

Having a large DB bufferpool helps this operation perform more optimally,
you need to keep an eye on the cache hit percent rate; we try to keep it
at >99%. [The longest time we took for expiration was about 3 days, which
was dire, when the DB bufferpool needed to be bigger!]

This is one of the serious limiting factors to the growth of an ADSM server
multi-threading the operation would help a lot ... any hope of that in
ADSM version 3 (please)?

Hope this helps. Regards, Sheelagh

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Sheelagh Treweek                         Email: sheelagh.treweek AT oucs.ox.ac 
DOT uk
Sheelagh Treweek                         Email: sheelagh.treweek AT oucs.ox.ac 
DOT uk
Oxford University Computing Services     Tel:   +44 (0)1865 273205
13 Banbury Road, Oxford, OX2 6NN, UK     Fax:   +44 (0)1865 273275
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