traditional MPI paradigm. The number of partitions of both modules is
typically equal to the number of processor P
although the i¡¯th elements of fluid module and solid module are not
connected geometrically in the simulation, they are glued together on the I¡¯th processor.
Charm++/AMPI framework, the two modules each get their own set of parallel
objects. And the size of the arrays are not restricted or related.
benefit of this is performance optimizations and better modularity.
due to the asynchronous method invocation, the flow of control is buried deep
into the object code