 
                                                                                | Article ID: | iaor20022022 | 
| Country: | Netherlands | 
| Volume: | 134 | 
| Issue: | 3 | 
| Start Page Number: | 648 | 
| End Page Number: | 663 | 
| Publication Date: | Nov 2001 | 
| Journal: | European Journal of Operational Research | 
| Authors: | Larsen Christian, Johnansen Sren Glud | 
| Keywords: | control processes, markov processes | 
We present an algorithm for computing a near-optimal service policy for a single-server queueing system when the service cost is a convex function of the service time. The policy has state-dependent service times, and it includes the options to remove jobs from the system and to let the server be off. The system's semi-Markov decision model has infinite action sets for the positive states. We design a new tailor-made policy-iteration algorithm for computing a policy for which the long-run average cost is at most a positive tolerance above the minimum average cost. For any positive tolerance our algorithm computes the desired policy in a finite (and small) number of iterations. The number is five for the numerical example used in the paper to illustrate results obtained by the algorithm.