You can use a Microsoft Excel spreadsheet to calculate the total JVM memory needed.
To calculate the amount of JVM Memory that you need:
Enter the dense and sparse dimension information into the dense and sparse dimension fields.
In Percentage of blocks that exist, run a select distinct query on the distinct combinations of sparse dimension members that exist in the historical tables.
In Block-Cache Memory Percentage, enter the percentage of the actual number of blocks in disk to be in the block-cache. As the percentage increases, the performance is enhanced, but you must then increase the memory.
The Excel spreadsheet calculates the required total JVM memory.