SPEL: Software tool for Porting E3SM Land Model with OpenACC in a Function Unit Test Framework

Conference · Tue Nov 01 04:00:00 EDT 2022

DOI:https://doi.org/10.1109/WACCPD56842.2022.00010· OSTI ID:1965230

Schwartz, Peter ^[1]; Wang, Dali ^[1]; Yuan, Fengming ^[1]; Thornton, Peter E. ^[1]

---

1. ORNL

Most high-end computers adopt hybrid architecture, porting a large-scale scientific code onto accelerators is necessary. The paper presents a generic method for porting large-scale scientific code onto accelerators using compiler directives within a modularized function unit test platform. We have implemented the method and designed a software tool (SPEL) to port the E3SM Land Model (ELM) onto the GPUs in the Summit computer. SPEL automatically generates GPU-ready test modules for all ELM functions, such as CanopyFlux, SoilTemperature, and EcosystemDynamics. SPEL breaks the ELM into a collection of standalone unit test programs for easy code verification and further performance improvement. We further optimize several ELM test modules with advanced techniques, including memory reduction, reconstructed parallel loops, and asynchronous GPU kernel launch. We hope our study will inspire new toolkit developments that expedite large-scale scientific code porting with compiler directives.

• Research Organization: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE; USDOE Office of Science (SC), Biological and Environmental Research (BER) (SC-23)
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 1965230
• Country of Publication: United States
• Language: English