Composition of Message Passing Interface Applications over MPICH-G2

Coupling grid applications requires code modification and high S/W engineering effort. We propose the Ensemble methodology in which message passing components are developed separately and applications, whether regular, irregular, SPMD or MPMD, are composed without component modification. Composed applications are pure Message Passing Interface programs running on MPICH-G2. We demonstrate our approach by developing two simplified atmospheric and ocean components, which may run on their own or coupled together (climate model) in any required configuration depending on geography or other design issues.