On vrijdag, feb 28, 2003, at 16:37 Europe/Amsterdam, Farren Minns wrote:
Hi All TSMers
I'm Running TSM 4.2.2.12 on a Solaris 2.7 server (E250 400Mhz, 1GB
mem). We
have been having severe performance issues recently and moved our
database
volumes off onto a new disk. To do this we formatted a new db volume
and
copy, and then we deleted the original ones. TSM immediately went into
action and moved the database volumes into the new volume.
The volume sizes were 5000Mb
2500Mb
1000Mb
After they each finished there was a summary that showed number of
bytes
moved. In this case the results were as follows:-
5000Mb - 947,912,704
2500Mb - 2,621,440,000
1000Mb - 1,048,576,000
Now I can see that the figures for the 1000 and 2500 are correct, but
the
5000 volume is way off! Any ideas why I am seeing this result. Is it
just a
bug or is the DB massively fragmented or something?
My guess is that you automatically allocate new db volumes as the db
grows, the biggest volume was created last, and was never filled, there
was never any need foor all of those pages....
I also guess all of these volumes were on one disk, as TSM tries to
allocate new pages in an RR fashion, this is a big performance hit.
Also, is there anyway to see if indeed the database is fragmented?
Fragmentation is not regularly an issue on a database... IN my
experience, fragmentation is just something we'll have to accept and
well, take into account when tuning a system. It cannot be helped and
ehhh, we don't like to go of-line a day/week just to unload+load db....
Many thanks to all who help as this is very puzzling.
All the best
Farren Minns - John Wiley & Sons Ltd
--
Met vriendelijke groeten,
Remco Post
SARA - Stichting Academisch Rekencentrum Amsterdam http://www.sara.nl
High Performance Computing Tel. +31 20 592 8008 Fax. +31 20 668 3167
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