Optimization of a Geophysical Application in GPU Through the Loop Tiling Technique

Abstract

This work aims to present the results obtained in optimizing a viscoacoustic geophysical model written with the DEVITO tool and optimized using the OpenACC tile directive for GPU execution. We compared three versions of the operator using the NVIDIA NCU profiling tool: Naive, Tiling (32,4,4), and Mixed Tiling. The Naive version does not use the loop tiling technique, the Tiling (32,4,4) version applies a tile of dimensions (32, 4, 4), and the Mixed Tiling version uses different tile sizes to other loop nests. Analyzing the experimental results, it is notable that the optimized versions substantially increase the cache hit rates and reduce the execution time by about 50%, attesting to the validity of the proposed solutions.