Dynamic multi-partitioning for parallel finite element applications

The DRAMA project 1 has been initiated to support the take-up of large scale parallel simulation in industry by dealing with the main problem which restricts the use of message passing simulation codes | the inability to perform dynamic load balancing. The central product of the project is a library comprising a variety of tools for dynamic repartitioning of unstructured Finite Element (FE) applications. The starting point for the DRAMA library is a discretisation mesh distribution into sub-domains that results in imbalanced costs of the application code. The core library functions then perform a parallel computation of a mesh re-allocation that will re-balance the costs based on the DRAMA cost model. We discuss the basic features of this cost model which allows a general approach to load identi cation, modelling and imbalance minimisation. First results are presented which show the necessity for multi-phase/multi-constraint partitioning components.