Sparse Matrix-Vector Multiplication Optimizations based on Matrix Bandwidth Reduction using NVIDIA CUDA

In this paper we propose the optimization of sparse matrix-vector multiplication (SpMV) with CUDA based on matrix bandwidth/profile reduction techniques. Computational time required to access dense vector is decoupled from SpMV computation. By reducing the matrix profile, the time required to access dense vector is reduced by 17% (for SP) and 24% (for DP). Reduced matrix bandwidth enables column index information compression with shorter formats, resulting in a 17% (for SP) and 10% (for DP) execution time reduction for accessing matrix data under ELLPACK format. The overall speedup for SpMV is 16% and 12.6% for the whole matrix test suite. The optimization proposed in this paper can be combined with other SpMV optimizations such as register blocking.