Optimal deadlock avoidance policy for reentrant work flows

Deadlock is a highly undesirable situation in which a set of parts or jobs are requested or waiting for resources held by other parts or jobs in the same set, with the set of parts or jobs in circular waiting. Although deadlock has attracted considerable attention in the context of automated manufacturing systems, most existing results focus on development of suboptimal deadlock avoidance algorithms to reduce the computational complexity involved. The paper considers a subclass of sequential processes whose optimal deadlock avoidance policy can be found in polynomial time. Our results include: (1)a re-entrant process model (2) analysis for single re-entrant process and (3)examples and extension to multiple work flows.