Improving ABT performance by adding synchronization points

Abstract

Asynchronous Backtracking (ABT) is a reference algorithm for Distributed CSP (DisCSP). In ABT, agents assign values to their variables and exchange messages asynchronously and concurrently. When an ABT agent sends a backtracking message, it continues working without waiting for an answer. In this paper, we describe a case showing that this strategy may cause some inefficiency. To overcome this, we propose ABT hyb , a new algorithm that results from adding synchronization points to ABT. We prove that ABT hyb is correct, complete and terminates. We also provide an empirical evaluation of the new algorithm on several benchmarks. Experimental results show that ABT hyb outperforms ABT. © 2008 Springer Berlin Heidelberg.