Regional Climate Model for the Lower Volga: Parallelization Efficiency Estimation

Alexander V. Titov, Alexander V. Khoperskov


We have deployed the regional climate model (RCM) RegCM 4.5 for the Lower Volga and adjacent territories with a horizontal spatial resolution of 20 km. The problems of choosing the computational domain in the RCM RegCM version 4.5 are considered. We demonstrate the influence of this factor on the forecast of rainfall distribution in the numerical simulations. The study of rainfall and snowfall is a more demanding test in comparison with temperature or pressure distributions. We investigate dependencies of calculation time, parallel speedup and parallelization efficiency on the number of processes for different multi-core CPUs. Our analysis of the efficiency of parallel implementation of RegCM for various multi-core and multi-processor systems show a strong dependence of the simulation speed on the CPU type. The best effect is achieved when the number of CPU threads and the number of parallel processes are equal. The parallel code speedup is in the range of 1.8 – 11 for different CPUs.

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Publishing Center of South Ural State University (454080, Lenin prospekt, 76, Chelyabinsk, Russia)