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arXiv · 2510.11513

An Asynchronous Many-Task Algorithm for Unstructured $S_{N}$ Transport on Shared Memory Systems

Alex Elwood·Tom Deakin·Justin Lovegrove·Chris Nelson
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Abstract

Discrete ordinates $S_N$ transport solvers on unstructured meshes pose a challenge to scale due to complex data dependencies, memory access patterns and a high-dimensional domain. In this paper, we review the performance bottlenecks within the shared memory parallelization scheme of an existing transport solver on modern many-core architectures with high core counts. With this analysis, we then survey the performance of this solver across a variety of compute hardware. We then present a new Asynchronous Many-Task (AMT) algorithm for shared memory parallelism, present results showing an increase in computational performance over the existing method, and evaluate why performance is improved.

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Alex Elwood, Tom Deakin, Justin Lovegrove, Chris Nelson. 2025-10-13. An Asynchronous Many-Task Algorithm for Unstructured $S_{N}$ Transport on Shared Memory Systems. https://arxiv.org/abs/2510.11513

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