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arXiv · 1809.04339

Concurrent Robin Hood Hashing

Robert Kelly·Barak A. Pearlmutter·Phil Maguire
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Abstract

In this paper we examine the issues involved in adding concurrency to the Robin Hood hash table algorithm. We present a non-blocking obstruction-free K-CAS Robin Hood algorithm which requires only a single word compare-and-swap primitive, thus making it highly portable. The implementation maintains the attractive properties of the original Robin Hood structure, such as a low expected probe length, capability to operate effectively under a high load factor and good cache locality, all of which are essential for high performance on modern computer architectures. We compare our data-structures to various other lock-free and concurrent algorithms, as well as a simple hardware transactional variant, and show that our implementation performs better across a number of contexts.

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Robert Kelly, Barak A. Pearlmutter, Phil Maguire. 2018-09-12. Concurrent Robin Hood Hashing. https://arxiv.org/abs/1809.04339

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