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DOE OSTI · 1525281

A 3D Parallel Algorithm for QR Decomposition

Ballard, Grey·Demmel, James·Grigori, Laura·Jacquelin, Mathias·Knight, Nicholas
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Abstract

Interprocessor communication often dominates the runtime of large matrix computations. Here, we present a parallel algorithm for computing QR decompositions whose bandwidth cost (communication volume) can be decreased at the cost of increasing its latency cost (number of messages). By varying a parameter to navigate the bandwidth/latency tradeoff, we can tune this algorithm for machines with different communication costs.

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97 MATHEMATICS AND COMPUTING

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Ballard, Grey, Demmel, James, Grigori, Laura, Jacquelin, Mathias, Knight, Nicholas. 2018-07-11. A 3D Parallel Algorithm for QR Decomposition. https://doi.org/10.1145/3210377.3210415

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