DEM-1: A Particle Simulation Machine for Efficient Short-Range Interaction Computations

This paper describes the architecture of high performance, particle simulation machine, DEM-1 for short-range particle interaction computations. All existing particle simulation machines have specialized pipelines to calculate long-range particle interactions effectively. However, their ability to perform particle simulations efficiently diminishes with short-range interactions. The communication cost component of particle simulations will play a significant role in performance when the computation cost becomes O(N). DEM-1's three dimensional torus high-speed network reduces the communication cost while 2048 local processors perform the time integration. The elimination of pipeline bubbles in DEM-1 is achieved by specially designed cut off judgment units. Each specialized pipeline consists of dedicated data path supported by position vector prefetch dual ported memory. The performance of DEM-1 will be presented with very large-scale Embedded Atom Method (EAM) molecular dynamics simulations.