Scalable 3D hybrid parallel Delaunay image-to-mesh conversion algorithm for distributed shared memory architectures

In this paper, we present a scalable three dimensional hybrid parallel Delaunay image-to-mesh conversion algorithm (PDR.PODM) for distributed shared memory architectures. PDR.PODM is able to explore parallelism early in the mesh generation process because of the aggressive speculative approach employed by the Parallel Optimistic Delaunay Mesh generation algorithm (PODM). In addition, it decreases the communication overhead and improves data locality by making use of a data partitioning scheme offered by the Parallel Delaunay Refinement algorithm (PDR). PDR.PODM supports fully functional volume element size grading and creates elements with varying element sizes. Small elements are created near boundary or inside the interested materials in order to capture the fine features while big elements are created in non-boundary or non-interested material regions to reduce the number of elements in the mesh. We tested PDR.PODM on Blacklight, a distributed shared memory (DSM) machine in Pittsburgh Supercomputing Center. For the uniform mesh generation, we observed a weak scaling speedup of 163.8 and above for up to 256 cores as opposed to PODM whose weak scaling speedup is only 44.7 on 256 cores. The end result is that we can generate 18 million elements per second as opposed to 14 million per ∗Corresponding author Email addresses: [email protected] (Daming Feng), [email protected] (Christos Tsolakis), [email protected] (Andrey N. Chernikov), [email protected] (Nikos P. Chrisochoides) Preprint submitted to Computer-Aided Design March 21, 2016 second in our earlier work. To the best of our knowledge, PDR.PODM exhibits the best scalability among parallel guaranteed quality Delaunay mesh generation algorithms running on DSM supercomputers. Compared to the uniform mesh generation, for the same geometric fidelity, the graded version sharply reduces the number of elements in the mesh and thus reduces the time to generate the mesh.