A Simple Release Policy for Networks of Queues with Controllable Inputs

In a recent paper, L. M. Wein (1992) addressed the problem of scheduling a network of queues. Given a multistation, multiclass queueing network, the problem involves deciding when to release a job to the network as well as how to sequence jobs at each machine in the network to meet a desired throughput level. By approximating this problem by a control problem involving Brownian motion, Wein derived effective heuristics, which easily outperformed traditional work release and sequencing rules. However, Wein's work release rules are complex and his sequencing rules are dynamic. In this paper, we test the performance of a simpler work release policy based on CONWIP (constant work-in-process) in conjunction with static sequencing rules. The results of our simulation study indicate that this simple work release rule can be effective.