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arXiv · 2105.12739

Task inefficiency patterns for a wave equation solver

Holger Schulz·Gonzalo Brito Gadeschi·Oleksandr Rudyy·Tobias Weinzierl
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Abstract

The orchestration of complex algorithms demands high levels of automation to use modern hardware efficiently. Task-based programming with OpenMP 5.0 is a prominent candidate to accomplish this goal. We study OpenMP 5.0's tasking in the context of a wave equation solver (ExaHyPE) using three different architectures and runtimes. We describe several task-scheduling flaws present in currently available runtimes, demonstrate how they impact performance and show how to work around them. Finally, we propose extensions to the OpenMP standard.

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Holger Schulz, Gonzalo Brito Gadeschi, Oleksandr Rudyy, Tobias Weinzierl. 2021-05-26. Task inefficiency patterns for a wave equation solver. https://doi.org/10.1007/978-3-030-85262-7_8

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