Parallelization and optimization of Saint-Venant solver on Sunway manycore processor.

The Saint-Venant equations can be used to describe the confluence process of unsteady flows in open channels. In largescale hydrological simulation software, solving the numerical solution of the equations is the biggest bottleneck restricting the running time of the program. This paper analyzes the structure of the serial solving program and the hotspots of calculation, and explores the parallelism of the singe-step simulation loop calculation section and instruction arrangement in the calculation intensive program. A master slave asynchronous parallel scheme is designed for the heterogeneous manicure architecture of the SunwaytTaihuLight supercomputer. The solver is ported, paired and accelerated based on MPI and thread libraries. SIMD technology is used to vectorize the slavecore's calculation section, and doubts buffering strategies are used to optimize the communication process. The tests show that the performance of hot functions can be increased by more than 3 times on average compared with the computation before optimization. Within a million-unit scale, the speedup of parallel programs using manicure optimization can maintain growing linearly, which shows strong scalability in Sunway's multi-nodes. [ABSTRACT FROM AUTHOR]