Performance analysis of Volna-OP2 – massively parallel code for tsunami modelling. (15th September 2020)

• Record Type: Journal Article
• Authors: Giles, Daniel; Kashdan, Eugene; Salmanidou, Dimitra M.; Guillas, Serge; Dias, Frédéric
• Is Part Of: Computers & fluids. Volume 209(2020)
• Publication Date: 2020-09-15
• Subjects: Tsunami modelling -- Finite-volume scheme -- Error analysis -- GPUs; Fluid dynamics -- Data processing -- Periodicals; 532.050285
• DOI: 10.1016/j.compfluid.2020.104649
• Languages: English
• ISSNs: 0045-7930

Abstract

Highlights: Comprehensive error analysis of a finite volume nonlinear shallow water solver. The effects of numerical dispersion and dissipation on modelling tsunami dynamics. Mesh size's role in the trade-off between runtime/accuracy for tsunami simulations. Performance scalability on a GPU cluster for a landslide induced tsunami. Abstract: The software package Volna-OP2 is a robust and efficient code capable of simulating the complete life cycle of a tsunami whilst harnessing the latest High Performance Computing (HPC) architectures. In this paper, a comprehensive error analysis and scalability study of the GPU version of the code is presented. A novel decomposition of the numerical errors into the dispersion and dissipation components is explored. Most tsunami codes exhibit amplitude smearing and/or phase lagging/leading, so the decomposition shown here is a new approach and novel tool for explaining these occurrences. To date, Volna-OP2 has been widely used by the tsunami modelling community. In particular its computational efficiency has allowed various sensitivity analyses and uncertainty quantification studies. Due to the number of simulations required, there is always a trade-off between accuracy and runtime when carrying out these statistical studies. The analysis presented in this paper will guide the user towards an acceptable level of accuracy within a given runtime.