Progress Towards Accelerating the Unified Model on Hybrid Multi-Core Systems

Conference · Thu Jul 01 04:00:00 EDT 2021

DOI:https://doi.org/10.1145/3468267.3470612· OSTI ID:1818722

Zhang, Wei ^[1]; Xu, Min ^[1]; Evans, Katherine ^[1]; Norman, Matthew ^[1]; Morales Hernandez, Mario ^[1]; Mahajan, Salil ^[1]

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1. ORNL

The cloud microphysics scheme, CASIM, and the radiation scheme, SOCRATES, are two computationally intensive parts within the Met Office's Unified Model (UM). This study enables CASIM and SOCRATES to use accelerated multi-core systems for optimal computational performance of the UM. Using profiling to guide our efforts, we refactored the code for optimal threading and kernel arrangement and implemented OpenACC directives manually or through the CLAW source-to-source translator. Initial porting results achieved 10.02x and 9.25x speedup in CASIM and SOCRATES respectively on 1 GPU compared with 1 CPU core. A granular performance analysis of the strategy and bottlenecks are discussed. These improvements will enable UM to run on heterogeneous computers and a path forward for further improvements is provided.

• Research Organization: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE; USDOE National Nuclear Security Administration (NNSA)
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 1818722
• Country of Publication: United States
• Language: English