Hybrid Parallelization of N-Body Simulations Involving Collisions and Self-Gravity.
Mark C. Lewis, Matthew Maly, Berna L. Massingill · 2009
Abstract – This paper explores the relative efficiency of multithreading versus message passing for numerical N-body simulations involving particle collisions and self-gravity. This tradeoff is becoming increasingly significant as the number of cores in commodity cluster nodes grows. We find that the choice of how to break up the workload can have significant impact on overall performance, with run times varying by as much as a factor of five. Unfortunately, however, there is no simple rule to help one determine if a particular simulation would be better served by using more threads or more processes. Simple rules, such as that message passing works better in more favorable geometries or that self-gravity is more favorable for multithreading are often applicable, but there are exceptions. Keywords: FIXME: A Maximum of 6 Keywords. 1