Speeding Up Finite Element Wave Propagation for Large-Scale Earthquake Simulations

Ricardo Taborda

Published 2010, SCEC Contribution #1416

This paper is concerned with the implementation and performance of a new approach to finite element earthquake simulations that represents a speedup factor of 3x in the total solving time employed by Hercules---the octree-based earthquake simulator developed by the Quake Group at Carnegie Mellon University. This gain derives from applying an efficient method for computing the stiffness contribution at the core of the solving algorithm for the discretized equations of motion. This efficient method is about 5 times faster than our previous conventional implementation---which had in itself held an advantageous position in the state-of-the-art in earthquake simulations. We evaluate the performance and scalability of the new implementation through numerical experiments under various problem sizes and resource conditions on up to 98K CPU cores, obtaining excellent results. These experiments required simulations with over 10 billion mesh elements. The newly obtained efficiency reveals that other areas in the code such as inter-processor communication, waiting time, and computing processes are amenable to further improvements. We believe that this latest advance has enormous implications for saving CPU hours and catapults the potential of Hercules to target larger and more complex problems, taking full advantage of the new generation of petascale supercomputers.

Citation
Taborda, R. (2010). Speeding Up Finite Element Wave Propagation for Large-Scale Earthquake Simulations. Oral Presentation at Carnegie Mellon University.