Frontier, a 1.5-exaflop system slated to be delivered to the OLCF in 2021, will feature AMD’s Radeon Instinct GPU accelerators.

Oscar Hernandez, tools developer in the Computer Science Research Group at the OLCF, gave an invited talk titled “Current Status on OpenACC Open Source Compilers and Their Evaluation.” Hernandez described the work that’s been done thus far on the GNU Compiler Collection (GCC) and the goals for achieving a performant, mature implementation of OpenACC.

Immediately before the conference, the OLCF issued a request for proposals to develop GCC and make OpenACC and OpenMP available for NVIDIA and AMD GPUs. GCC was the most frequently used compiler on the OLCF’s Jaguar and Titan systems as well as the most frequently used compiler on Summit during the supercomputer’s first year of production.

“GCC is where a lot of projects start, and once people start using a compiler suite, there’s inertia for them to continue,” Wells said. “With the idiosyncrasies from one compiler to the next and within the codes themselves, it becomes challenging to get a complex code to compile in more than one compiler.”

Wells and Hernandez also participated in the technical and executive meetings at the conference. Wells was recently elected vice president of the organization, and Hernandez serves as a member of the OpenACC board of directors.

“In accepting the role of vice president of, I gained the ability to give a voice to the goals for this standard both inside and outside of the organization,” Wells said. “We are beginning to articulate a long-term vision for OpenACC, and that’s something I believe is important for DOE’s LCFs to be a part of as we move into the exascale era.”

The OLCF’s call for proposals to develop GCC will remain open until September 20.

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Source: Rachel Harken, Oak Ridge National Laboratory