Hello Reddy
Check how much memory is assigned to the database.
Find out how much memory assigned for components like SGA, PGA, etc
You can check from the SQL using these
show parameter sga
show parameter pga
Check the memory assigned used by the SAP system
Run sappfpar against the instance profile of the SAP system to see the memory allocation for SAP.
You should also check the page file configuration on Windows.
Regards
RB