The K-Truss of a graph is a cohesive subgraph that has been widely used for community detection in applications such as social networks and security analysis. In this paper, we first propose one optimized triangle search kernel with a few operations that can be used in both triangle counting and triangle search to replace the existing list intersection method. Based on the optimized kernel, three truss analytics algorithms, an optimized K-Truss parallel algorithm, a maximal K-Truss parallel algorithm, and a Truss decomposition parallel algorithm, are developed to efficiently enable different kinds of graph analysis. Moreover, all proposed parallel algorithms have been implemented in the highly-productive parallel language Chapel and integrated into the open-source framework Arkouda. Experimental results compared with the existing list intersection-based method show that for both synthetic and real-world graphs, the proposed method can significantly improve the performance of truss analysis on large graphs. The implemented method is publicly available from GitHub.
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Truss-based Community Search: a Truss-equivalence Based Indexing Approach
We consider the community search problem defined upon a large graph G: given a query vertex q in G, to find as output all the densely connected subgraphs of G, each of which
contains the query v. As an online, query-dependent variant of the well-known community detection problem, community search enables personalized community discovery that has found widely varying applications in real-world, large-scale graphs. In this paper, we study the community search problem in the truss-based model aimed at discovering all dense and cohesive k-truss communities to which the query vertex q belongs. We introduce a novel equivalence relation, k-truss equivalence, to model the intrinsic density and cohesiveness of edges in k-truss communities. Consequently, all the edges of G can be partitioned to a series of k-truss equivalence classes that constitute a space-efficient, truss-preserving index structure, EquiTruss. Community search can be henceforth addressed directly upon EquiTruss without repeated, time-demanding accesses to the original graph, G, which proves to be theoretically optimal. In addition, EquiTruss can be efficiently updated in a dynamic fashion when G evolves with edge insertion and deletion. Experimental studies in real-world, large-scale graphs validate the efficiency and effectiveness of EquiTruss, which has achieved
at least an order of magnitude speedup in community search over the state-of-the-art method, TCP-Index.
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- Award ID(s):
- 1743142
- PAR ID:
- 10057533
- Date Published:
- Journal Name:
- Proceedings of the VLDB Endowment
- Volume:
- 10
- Issue:
- 11
- ISSN:
- 2150-8097
- Page Range / eLocation ID:
- 1298-1309
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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In graph analytics, a truss is a cohesive subgraph based on the number of triangles supporting each edge. It is widely used for community detection applications such as social networks and security analysis, and the performance of truss analytics highly depends on its triangle counting method. This paper proposes a novel triangle counting kernel named Minimum Search (MS). Minimum Search can select two smaller adjacency lists out of three and uses fine-grained parallelism to improve the performance of triangle counting. Then, two basic algorithms, MS-based triangle counting, and MS-based support updating are developed. Based on the novel triangle counting kernel and the two basic algorithms above, three fundamental parallel truss analytics algorithms are designed and implemented to enable different kinds of graph truss analysis. These truss algorithms include an optimized K-Truss algorithm, a Max-Truss algorithm, and a Truss Decomposition algorithm. Moreover, all proposed algorithms have been implemented in the parallel language Chapel and integrated into an open-source framework, Arkouda. Through Arkouda, data scientists can efficiently conduct graph analysis through an easy-to-use Python interface and handle large-scale graph data in powerful back-end computing resources. Experimental results show that the proposed methods can significantly improve the performance of truss analysis on real-world graphs compared with the existing and widely adopted list intersection-based method. The implemented code is publicly available from GitHub (https://github.com/Bears-R-Us/arkoudanjit). }more » « less
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- The DOI is not currently available.
