Performance of Hybrid Message-Passing and Shared-Memory Parallelism for Discrete Element Modeling

The current trend in HPC hardware is towards clusters of shared-memory (SMP) compute nodes. For applications developers the major question is how best to program these SMP clusters. To address this we study an algorithm from Discrete Element Modeling, parallelised using both the message-passing and shared-memory models simultaneously (“hybrid” parallelisation). The natural loadbalancing methods are different in the two parallel models, the shared-memory method being in principle more efficient for very load-imbalanced problems. It is therefore possible that hybrid parallelism will be beneficial on SMP clusters. We benchmark MPI and OpenMP implementations of the algorithm on MPP, SMP and cluster architectures, and evaluate the effectiveness of hybrid parallelism. Although we observe cases where OpenMP is more efficient than MPI on a single SMP node, we conclude that our current OpenMP implementation is not yet efficient enough for hybrid parallelism to outperform pure message-p...

• Type: Conference
• Year: 2000
• Where: SC
• Authors: D. S. Henty
• Keywords: Applied Computing, Hybrid Parallelism, SC 2000, SMP Clusters, Smp Nodes