A Safe Algorithm for Resolving OR Deadlocks

Deadlocks in the OR model are usually resolved by aborting a deadlocked process. Prior algorithms for the same model sometimes abort nodes needlessly wasting computing resources. This paper presents a new deadlock resolution algorithm for the OR model that satisfies the following correctness criteria: (Safety) the algorithm does not resolve false deadlocks; (Liveness) the algorithm resolves all deadlocks in finite time. The communication cost of the algorithm is similar to that of previous nonsafe proposals. The theoretical cost has been validated by simulation. In addition, different algorithm initiation alternatives have been analyzed in order to reduce the latency of deadlocks.