Dynamic load balancing for predictions of storm surge and coastal flooding. (June 2021)

• Record Type: Journal Article
• Authors: Roberts, Keith J.; Casey Dietrich, J.; Wirasaet, Damrongsak; Pringle, William J.; Westerink, Joannes J.
• Is Part Of: Environmental modelling & software. Volume 140(2021)
• Publication Date: 2021-06
• Subjects: Storm surge -- Coastal flooding -- Dynamic load balancing -- Finite element modeling -- Zoltan toolkit -- ParMETIS; Environmental monitoring -- Computer programs -- Periodicals; Ecology -- Computer simulation -- Periodicals; Digital computer simulation -- Periodicals; Computer software -- Periodicals; Environmental Monitoring -- Periodicals; Computer Simulation -- Periodicals; Environnement -- Surveillance -- Logiciels -- Périodiques; Écologie -- Simulation, Méthodes de -- Périodiques; Simulation par ordinateur -- Périodiques; Logiciels -- Périodiques; Computer software; Digital computer simulation; Ecology -- Computer simulation; Environmental monitoring -- Computer programs; Periodicals; Electronic journals; 363.70015118
• DOI: 10.1016/j.envsoft.2021.105045
• Languages: English
• ISSNs: 1364-8152

Abstract

Abstract: As coastal circulation models have evolved to predict storm-induced flooding, they must include progressively more overland regions that are normally dry, to where now it is possible for more than half of the domain to be needed in none or only some of the computations. While this evolution has improved real-time forecasting and long-term mitigation of coastal flooding, it poses a problem for parallelization in an HPC environment, especially for static paradigms in which the workload is balanced only at the start of the simulation. In this study, a dynamic rebalancing of computational work is developed for a finite-element-based, shallow-water, ocean circulation model of extensive overland flooding. The implementation has a low overhead cost, and we demonstrate a realistic hurricane-forced coastal flooding simulation can achieve peak speed-ups near 45% over the static case, thus operating now at 80−90 % efficiency. Highlights: Load balancing reduces prediction time for coastal flooding by up to 45%. The floodplain portion of the mesh is dynamically removed from calculations. Performance depends significantly on selected rebalancing heuristics.