A large-scale metacomputing framework for the ModSAF real-time simulation

A distributed, parallel implementation of the widely-used Modular Semi-Automated Forces (ModSAF) Distributed Interactive Simulation (DIS) is presented, with Scalable Parallel Processors (SPPs) used to simulate more than 50,000 individual vehicles. The single-SPP version is described and shown to be scalable. This code is portable and has been run on a variety of different SPP architectures. Results for simulations with up to 15,000 vehicles are presented for a number of distinct SPP architectures. The initial multi-SPP (metacomputing) run used explicit Gateway communication processes to exchange data among several SPPs simulating separate portions of the full battle space. The 50K-vehicle simulations utilized 1904 processors on SPPs at six sites across seven time zones, including platforms from three computer manufacturers. (Four of the SPP sites in the large run used the single-SPP code described in this work, with a somewhat different single-SPP ModSAF implementation used at the other two sites.) Particular attention is given to analyses of inter-SPP data rates and Gateway performance in the multi-SPP runs. An alternative, next-generation implementation based on Globus is presented, including discussions of initial experiments, comparisons to the Gateway model, and planned near-term extensions. Finally, comparisons are made between this work and ongoing mainstream DIS activities. (C) 1998 Elsevier Science B.V. All rights reserved.