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From "Brian Spindler" <bspind...@netuitive.com>
Subject derby performance
Date Wed, 26 Aug 2009 20:09:02 GMT
Hi all, 

For Both Questions: Data and Log are on same drive and separating isn't
really an option, we're using embedded version.

+---Question #1 ---------+
I have an operation consisting of deleting 125K rows from 3 tables,
first table takes 50s, second table takes >6mins and the third 2.5min.
11min total so I have 2min worth of optimizing just on JAVA side but I
can't seem to make any headway on optimizing derby performance.

I'm using 10.4, Embedded version; my question is why the differences in
time?  I've got my system pretty isolated and I can see the disk is
pegged but other than a max of 5column difference the tables are
similar.  The deletes are all executed and then committed in at the end.

+---Question #2 ---------+
Seems I have a similar problem for inserting into the database,
inserting take on order of 7mins to get all rows into database.  In this
case all rows inserted in random chunks across all three tables but
again, I can see disk pegged but from logs it seems Derby is fast then
slow, and then fast again.  

I'm running with mainly all defaults, PreparedStatements are reused
across insert operations. 

Any thoughts? 



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