Time-Domain BEM for the Wave Equation: Optimization and Hybrid Parallelization

International audienceThe problem of time-domain BEM for the wave equation in acoustics and electromagnetism can be expressed as a sparse linear system composed of multiple interaction/convolution matrices. It can be solved using sparse matrix-vector products which are inefficient to achieve high Flop-rate. In this paper we present a novel approach based on the re-ordering of the interaction matrices in slices. We end up with a custom multi-vectors/vector product operation and compute it using SIMD intrinsic functions. We take advantage of the new order of the computation to parallelize in shared and distributed memory. We demonstrate the performance of our system by studying the sequential Flop-rate and the parallel scalability, and provide results based on an industrial test-case with up to 32 nodes