Performance prediction through simulation of a hybrid MPI/OpenMP application

This paper deals with the performance prediction of hybrid MPI/OpenMP code. The use of HeSSE (Heterogeneous System Simulation Environment), along with an XML-based prototype language, MetaPL, makes it possible to predict hybrid application performance in many different working conditions, e.g., without the fully developed code or in an unavailable system. After a review of hybrid programming techniques and a brief overview of the HeSSE simulation environment, the problems related to the simulation of hybrid code and to its description through trace files are dealt with. The whole application modeling and analysis cycle is presented and validated, predicting the performance of a parallel N-body code on a SMP cluster and comparing it to the timings measured on the real system.