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arXiv · 1602.05232

Work-Efficient Parallel and Incremental Graph Connectivity

Natcha Simsiri·Kanat Tangwongsan·Srikanta Tirthapura·Kun-Lung Wu
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Abstract

On an evolving graph that is continuously updated by a high-velocity stream of edges, how can one efficiently maintain if two vertices are connected? This is the connectivity problem, a fundamental and widely studied problem on graphs. We present the first shared-memory parallel algorithm for incremental graph connectivity that is both provably work-efficient and has polylogarithmic parallel depth. We also present a simpler algorithm with slightly worse theoretical properties, but which is easier to implement and has good practical performance. Our experiments show a throughput of hundreds of millions of edges per second on a $20$-core machine.

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Natcha Simsiri, Kanat Tangwongsan, Srikanta Tirthapura, Kun-Lung Wu. 2016-02-16. Work-Efficient Parallel and Incremental Graph Connectivity. https://arxiv.org/abs/1602.05232

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