Abstract
Recently Avis and Jordan have demonstrated the efficiency of a simple technique called budgeting for the parallelization of a number of tree search algorithms. The idea is to limit the amount of work that a processor performs before it terminates its search and returns any unexplored nodes to a master process. This limit is set by a critical budget parameter which determines the overhead of the process. In this paper we study the behaviour of the budget parameter on conditional Galton–Watson trees obtaining asymptotically tight bounds on this overhead. We present empirical results to show that this bound is surprisingly accurate in practice.
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Notes
All computational results in the paper were obtained on mai20 at Kyoto University: 2x Xeon E5-2690 (10-core 3.0GHz), 20 cores, 128GB memory, 3TB hard drive.
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Acknowledgements
We gratefully acknowledge helpful conversations with Louigi Addario-Berry and Charles Jordan. The research of Avis was supported by a JSPS Grant No. (24300002) Kakenhi Grant and a Grant-in-Aid for Scientific Research on Innovative Areas, ‘Exploring the Limits of Computation (ELC)’. The research of Devroye was supported by the Natural Sciences and Engineering Research Council of Canada.
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Avis, D., Devroye, L. An Analysis of Budgeted Parallel Search on Conditional Galton–Watson Trees. Algorithmica 82, 1329–1345 (2020). https://doi.org/10.1007/s00453-019-00645-x
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DOI: https://doi.org/10.1007/s00453-019-00645-x