An improved lower bound for the time complexity of mutual exclusion

James H. Anderson, Yong-Jik Kim
2001 Proceedings of the twentieth annual ACM symposium on Principles of distributed computing - PODC '01  
We establish a lower bound of Ω(log N/ log log N ) remote memory references for N -process mutual exclusion algorithms based on reads, writes, or comparison primitives such as test-and-set and compare-and-swap. Our bound improves an earlier lower bound of Ω(log log N/ log log log N ) established by Cypher. Our lower bound is of importance for two reasons. First, it almost matches the Θ(log N ) time complexity of the best known algorithms based on reads, writes, or comparison primitives. Second,
more » ... our lower bound suggests that it is likely that, from an asymptotic standpoint, comparison primitives are no better than reads and writes when implementing local-spin mutual exclusion algorithms. Thus, comparison primitives may not be the best choice to provide in hardware if one is interested in scalable synchronization.
doi:10.1145/383962.383996 dblp:conf/podc/AndersonK01 fatcat:azsdbavmjfcyxkyk7vxgpwzqwu