Performance prediction of N-body simulations on a hybrid architecture

Hybrid Architectures consist of Special Purpose Devices (SPD) used in conju nction with parallel computers. They have the potential of being a major co mputing, tool for various applications of Computational Science. Mapping th e application tasks to the hybrid machine is not trivial, and bottlenecks c an arise quite easily. Performance Modeling is a suitable method to tackle this problem. The performance model presented here simulates the activity o f GRAPE, a very powerful SPD used in Computational Astrophysics, in conjunc tion with a general purpose host. We show how our model faithfully reproduc es the behaviour of the real hybrid machine. We also present some examples of how our model can be used to predict performance improvements. (C) 2001 Elsevier Science B.V. All rights reserved.