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arXiv · 1112.4539

Implementation of a Parallel Tree Method on a GPU

Naohito Nakasato
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Abstract

The kd-tree is a fundamental tool in computer science. Among other applications, the application of kd-tree search (by the tree method) to the fast evaluation of particle interactions and neighbor search is highly important, since the computational complexity of these problems is reduced from O(N^2) for a brute force method to O(N log N) for the tree method, where N is the number of particles. In this paper, we present a parallel implementation of the tree method running on a graphics processing unit (GPU). We present a detailed description of how we have implemented the tree method on a Cypress GPU. An optimization that we found important is localized particle ordering to effectively utilize cache memory. We present a number of test results and performance measurements. Our results show that the execution of the tree traversal in a force calculation on a GPU is practical and efficient.

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Naohito Nakasato. 2011-12-20. Implementation of a Parallel Tree Method on a GPU. https://doi.org/10.1016/j.jocs.2011.01.006

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