Subgraph Querying with Parallel Use of Query Rewritings and Alternative Algorithms

Katsarou, F., Ntarmos, N. and Triantafillou, P. (2017) Subgraph Querying with Parallel Use of Query Rewritings and Alternative Algorithms. In: International Conference on Extending Database Technology (EDBT) 2017, Venice, Italy, 21-24 March 2017, pp. 25-36. ISBN 9783893180738 (doi: 10.5441/002/edbt.2017.04)

130142.pdf - Accepted Version
Available under License Creative Commons Attribution Non-commercial No Derivatives.



Subgraph queries are central to graph analytics and graph DBs. We analyze this problem and present key novel discoveries and observations on the nature of the problem which hold across query sizes, datasets, and top-performing algorithms. Firstly, we show that algorithms (for both the decision and matching versions of the problem) suffer from straggler queries, which dominate query workload times. As related research caps query times not reporting results for queries exceeding the cap, this can lead to erroneous conclusions of the methods' relative performance. Secondly, we study and show the dramatic effect that isomorphic graph queries can have on query times. Thirdly, we show that for each query, isomorphic queries based on proposed query rewritings can introduce large performance benefits. Fourthly, that straggler queries are largely algorithm-specific: many challenging queries to one algorithm can be executed efficiently by another. Finally, the above discoveries naturally lead to the derivation of a novel framework for subgraph query processing. The central idea is to employ parallelism in a novel way, whereby parallel matching/decision attempts are initiated, each using a query rewriting and/or an alternate algorithm. The framework is shown to be highly beneficial across algorithms and datasets.

Item Type:Conference Proceedings
Glasgow Author(s) Enlighten ID:Katsarou, Foteini and Triantafillou, Professor Peter and Ntarmos, Dr Nikos
Authors: Katsarou, F., Ntarmos, N., and Triantafillou, P.
College/School:College of Science and Engineering > School of Computing Science
Copyright Holders:Copyright © 2016 The Authors
Publisher Policy:Reproduced under a Creative Commons License
Related URLs:

University Staff: Request a correction | Enlighten Editors: Update this record