Case studies on GPU usage and data structure design

Big improvements in the performance of graphics processing units (GPUs) turned them into a compelling platform for high performance computing. In this thesis, we discuss the usage of NVIDIA’s CUDA in two applications – Einstein@Home, a distributed computing software, and OpenSteer, a game-like application. Our work on Einstein@Home demonstrates that CUDA can be integrated into existing applications with minimal changes, even in programs, which have been designed without considering GPU usage. However the existing data structure of Einstein@Home performs poorly when used at the GPU. We demonstrate that using a redesigned data structure improves the performs to about three-times as fast as the original CPU version, even though the code executed at the device is not optimized. We further discuss the design of a novel spatial data structure called dynamic grid, which is optimized for CUDA usage. We measure its performance by integrating it into the Boids scenario of OpenSteer. Our new concept outperforms a uniform grid by a margin of up to 15%, even though the dynamic grid still provides optimization potential.