PISim: A parallelization framework for interaction simulations

Abstract

This paper presents PISim, a Parallelization framework for Interaction Simulations. PISim can be used to simulate models of short ranged object interactios in space on high-performance computers. By using PISim, users can avoid the difficulties and complexity usually involved in porting sequential sourcecode to parallel machines. The framework achieves this by combining severals fast and simple elements: First, it uses an efficient representation of space (a helical array) which exploits temporal continuity, second, it uses a straightforward way of communica- tion between processors by means of message passing, third, it arranges simulation domains in cell clusters that are treated as individual objects, fourth, it monitors the computation times of each cluster continuously and uses model based control to grow or shrink the clusters as needed to balance the load between processors, and fifth, it encapsulates and hides all this complexity from the user by using programming templates to provide a slim interface for end users. This small interface makes it possible to adopt the framework easily to new problems. It quickens development cyles and therby enables users not familiar with parallel programming techniques to adapt rapid prototyping paradigms.