Acceleration of the space-time boundary element method using GPUs

Abstract

In this thesis we aim at accelerating the space-time boundary element method for the heat equation using GPUs. Contrary to the time-stepping approaches, the method assembles the global space-time system matrices, which have large memory requirements. This limits the size of problems that can be solved. Starting from the existing CPU implementation in the BESTHEA library, we develop a GPU-accelerated code that computes the matrix values during the matrix-vector multiplication on the fly as they are needed. This enables us to solve large problems even on GPU accelerators with limited amount of memory, since the matrices do not have to be assembled and stored. Using this approach we achieved a speedup in the order of tens with respect to the original CPU code and were able to solve significantly larger problems.