Calculate blockSize parameter in JRSwapFile

[piovezan]

Hi,

I'm using virtualization (net.sf.jasperreports.engine.fill.JRSwapFileVirtualizer) with some large reports, but my application is still subject to OOEM (java.lang.OutOfMemoryError). After some profiling I have come to the conclusion that most data in the heap is allocated by the swap file handling mechanism (accounting of free blocks and such). This may be related to ( this known bug - obsolete link deleted ), as reports do have subreports, however I also suspect of a poor choice on the virtualization parameters (maxSize for JRSwapFileVirtualizer, and blockSize and minGrowCount for JRSwapFile). I'm specially suspicious of the block size parameter, but haven't been able to find a good formula to calculate it based on the report page contents. Is there such formula, at least for coming up with an approximate value?

Thanks,

Rodrigo Piovezan

[lucianc]

Sounds like you are using a small block size.  A typical block size would be in the range of kilos, you can start with something like 4096 for instance.

Regards,

Lucian