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arXiv · 1906.04120

Parallel Streaming Random Sampling

Kanat Tangwongsan·Srikanta Tirthapura
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Abstract

This paper investigates parallel random sampling from a potentially-unending data stream whose elements are revealed in a series of element sequences (minibatches). While sampling from a stream was extensively studied sequentially, not much has been explored in the parallel context, with prior parallel random-sampling algorithms focusing on the static batch model. We present parallel algorithms for minibatch-stream sampling in two settings: (1) sliding window, which draws samples from a prespecified number of most-recently observed elements, and (2) infinite window, which draws samples from all the elements received. Our algorithms are computationally and memory efficient: their work matches the fastest sequential counterpart, their parallel depth is small (polylogarithmic), and their memory usage matches the best known.

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Kanat Tangwongsan, Srikanta Tirthapura. 2019-06-10. Parallel Streaming Random Sampling. https://arxiv.org/abs/1906.04120

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