Hi Venkata,
According to my understanding with purge policy is concerned, the purge policy
ENTIRE POOL will provide more benefits and enhance the performance in websphere..
Please find more details about the purge policy below..
ENTIRE POOL :
If you set the purge policy for this data source object to EntirePool, all connections in the pool are marked stale. Any connection not in use is immediately closed. A connection in use is closed and throws a StaleConnectionException during the next operation on that connection. Subsequent getConnection requests from the application result in new connections to the database opening. When using this purge policy, there is a slight possibility that some connections in the pool are closed unnecessarily when they are not stale. However, this is a rare occurrence. In most cases, a purge policy of EntirePool is the best choice.
FAILING CONNECTION ONLY:
If you set the purge policy for this data source object to FailingConnectionOnly, only the connection that caused the StaleConnectionException is closed. While this setting eliminates the possibility that valid connections are closed unnecessarily, it makes recovery from an application perspective more complicated. Because only the currently failing connection is closed, there is a good possibility that the next getConnection request from the application can return a connection from the pool that is also stale, resulting in more stale connection exceptions.
Hope this helps..
Thanks and Regards,
Pavan A