RE: Performance when using POI to create an excel workbook.

 
I haven't looked at the code in question - but how often are you triggering
garbage collection?  It seems to me that this is one area for possible
tuning opportunities since the performance of the Java will likely decline
the more "garbage" there is lying around.  Similarly triggering collection
more often than needed may adversely affect performance.

Another consideration if you have some Java skills would be to introduce
some simple Java classes for common action groups like create cell, set
contents, etc.  JNI is not the most efficient mechanism in the world (to put
it mildly) so when setting values in a string cell for example, having a
Java method that would accept an RPG char string and create the string and
do all of the twiddly bits has to work a lot faster than going through the
JNI interface multiple times.  Just simple routines to handle char and num
cells would probably provide a significant boost and can't be that hard to
write.

Jon Paris
Partner400

www.Partner400.com
www.RPGWorld.com