The scaling of molecular dynamics on the KSR1

Molecular dynamics and many other particle based simulation techniques are often highly parallelizable in principle. In practice many algorithms for concurrency can lead to irreproducible trajectories. We suggest a method for providing reproducible simulations that suffers only a small performance penalty. Results for scaling of the molecular dynamics code ESP to the KSR1 parallel computer are also given and the effects of trying to overlap computation and communication on the KSR are discussed. Algorithms are discussed with particular attention focused on the force summation aspects