Efficient utilization of memory hierarchy to enable the computation on bigger domains for stencil computation in CPU-GPU based systems

The problem size of the stencil computation is limited by the memory capacity GPU, which is typically smaller than that of CPU memory in CPU-GPU based super computers. To enable bigger domain computation while maintaining high performance, this paper proposes and evaluates optimization methods for stencil computation by efficient utilization of the memory hierarchy in those systems. It uses temporal blocking method to enable bigger domain computation on GPU. Then, it uses buffer-copy method to solve redundancy problem of temporal blocking method. To solve the space consumption problem of buffer-copy method on GPU side, it sets buffer on the CPU side. Evaluation of stencil simulation on 3D domain shows that our new method for 7-point and 13-point stencils achieves good performance which is 1.22 times and 1.28 times higher than other methods on average.