Hi.. I am writing a standalone batch application ... It is multithreaded and the expected DB transactions per second is around 2000.. It primarily is written with Oracle 10g .... but ideally should be database independent... Since I have no server runtime ... I can't use container managed connection pools.... The open source option which I saw is apache commons DBCP... I just want to explore the scalability of DBCP ... or is there a better connection pooler for Oracle (with vendor specific optimizations).... Performance has higher priority than database portabilty for me.