Optimization strategies using hybrid MPI+OpenMP parallelization for large-scale data visualization on earth simulator

Abstract

An efficient parallel visualization library has been developed for the Earth Simulator. Due to its SMP cluster architecture, a three-level hybrid parallel programming model, including message passing for inter-SMP node communication, loop directives by OpenMP for intra-SMP node parallelization and vectorization for each processing element (PE) was adopted. In order to get good speedup performance with OpenMP parallelization, many strategies are used in implementing the visualization modules such as thread parallelization by OpenMP considering seed point distributions and flow features for parallel streamline generation, multi-coloring reordering to avoid data race of shared variables, some kinds of coherence removal, and hybrid image-space and object-space parallel for volume rendering. Experimental results on the Earth Simulator demonstrate the feasibility and effectiveness of our methods. © 2008 Springer-Verlag.