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arXiv · 2404.16517

Scalable Distributed String Sorting

Florian Kurpicz·Pascal Mehnert·Peter Sanders·Matthias Schimek
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Abstract

String sorting is an important part of tasks such as building index data structures. Unfortunately, current string sorting algorithms do not scale to massively parallel distributed-memory machines since they either have latency (at least) proportional to the number of processors $p$ or communicate the data a large number of times (at least logarithmic). We present practical and efficient algorithms for distributed-memory string sorting that scale to large $p$. Similar to state-of-the-art sorters for atomic objects, the algorithms have latency of about $p^{1/k}$ when allowing the data to be communicated $k$ times. Experiments indicate good scaling behavior on a wide range of inputs on up to 49152 cores. Overall, we achieve speedups of up to 5 over the current state-of-the-art distributed string sorting algorithms.

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Florian Kurpicz, Pascal Mehnert, Peter Sanders, Matthias Schimek. 2024-04-25. Scalable Distributed String Sorting. https://arxiv.org/abs/2404.16517

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