A survey of parallel local search for SAT

Abstract

Local search algorithms are widely used to tackle combinatorial problems in several domains, one of the main features of these algorithms lies in the fact that they can tackle very large problems. Moreover, an interesting possibility is the potential speedup obtained by executing multiple copies of the sequential algorithm. In this paper, we review the current state-of-the art and future trends of parallel local search algorithms for the SAT problem, one the most important NP-complete problems. Generally speaking these algorithms can be broadly classified into two categories: parallel portfolios, where several algorithms compete and cooperate to solve a given problem instance and multi-flip algorithms where several flips of the variables are performed at the same time.