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arXiv · 1905.13376

Efficient Multiway Hash Join on Reconfigurable Hardware

Kunle Olukotun·Raghu Prabhakar·Rekha Singhal·Jeffrey D. Ullman·Yaqi Zhang
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Abstract

We propose the algorithms for performing multiway joins using a new type of coarse grain reconfigurable hardware accelerator~-- ``Plasticine''~-- that, compared with other accelerators, emphasizes high compute capability and high on-chip communication bandwidth. Joining three or more relations in a single step, i.e. multiway join, is efficient when the join of any two relations yields too large an intermediate relation. We show at least 200X speedup for a sequence of binary hash joins execution on Plasticine over CPU. We further show that in some realistic cases, a Plasticine-like accelerator can make 3-way joins more efficient than a cascade of binary hash joins on the same hardware, by a factor of up to 45X.

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Kunle Olukotun, Raghu Prabhakar, Rekha Singhal, Jeffrey D. Ullman, Yaqi Zhang. 2019-05-31. Efficient Multiway Hash Join on Reconfigurable Hardware. https://arxiv.org/abs/1905.13376

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