HOSA: Fast Distributed Triangle Enumerating On Tera-Edge Graphs

Distributed triangle enumerating has attracted a lot of interest for the capability to process large graphs quickly. However, existing solutions usually suffer from low speed and/or poor graph-size scalability due to the massive short messages passed via the network or the huge amount of intermediate data. To address the issues, we propose HOSA, a distributed out-of-core triangle enumerating algorithm. HOSA first introduces an I/O-efficient graph placement strategy to divide and place a graph across a cluster in a load-balanced manner to reduce intermediate data and exploit the aggregated I/O bandwidth of the cluster. To enumerate triangles, HOSA proposes an efficient algorithm which not only eliminates short messages, the main cause of the low speed of most previous works, but also effectively uses the aggregated network and I/O bandwidths to further improve performance, and achieves high speed and graph-size scalability. Extensive evaluations show that HOSA can process much larger graphs with better or at least comparable speed than state-of-the-art algorithms, including the best distributed-memory algorithm LiteTE.