Hi Anup,
You are processing more data than in your program than is currently allocated to a process in your system. So the process runs out of memory and the program ends with a dump.
1) Try to keep global data to a minimum in your program.
2) Only bring the data you require from the DB for processing (i.e. change any select all statements and add as many where clauses as possible)
3) If you are still running out of memory, then you will need to process your data volume in batches, which will require a few changes to your program.
You can request technical team to increase memory allocation to processes (if available), but you should use this as a last resort, where none of the above options results in the necessary improvements required.
Hope that helps..
Katan