Tight Analysis of Parallel Randomized Greedy MIS
Tight Analysis of Parallel Randomized Greedy MIS
复制标题
并行随机贪婪MIS的严格分析
DOI:
10.1145/3326165
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发表时间:
2017
期刊:
影响因子:
--
通讯作者:
A. Noever
中科院分区:
文献类型:
--
作者:
Manuela Fischer;A. Noever
We provide a tight analysis that settles the round complexity of the well-studied parallel randomized greedy MIS algorithm, thus answering the main open question of Blelloch, Fineman, and Shun [SPAA’12]. The parallel/distributed randomized greedy Maximal Independent Set (MIS) algorithm works as follows. An order of the vertices is chosen uniformly at random. Then, in each round, all vertices that appear before their neighbors in the order are added to the independent set and removed from the graph along with their neighbors. The main question of interest is the number of rounds it takes until the graph is empty. This algorithm has been studied since 1987, initiated by Coppersmith, Raghavan, and Tompa [FOCS’87], and the previously best known bounds were O(log n) rounds in expectation for Erdős-Rényi random graphs by Calkin and Frieze [Random Struc. Alg.’90] and O(log2 n) rounds with high probability for general graphs by Blelloch, Fineman, and Shun [SPAA’12]. We prove a high probability upper bound of O(log n) on the round complexity of this algorithm in general graphs and that this bound is tight. This also shows that parallel randomized greedy MIS is as fast as the celebrated algorithm of Luby [STOC’85, JALG’86].