We explore whether dynamically reassigning servers to parallel queues in response to queue imbalances can reduce average waiting time in those queues. We use approximate dynamic programming methods to determine when servers should be switched, and we compare the performance of such dynamic allocations to that of a pre-scheduled deterministic allocation. Testing our method on both synthetic data and data from airport security checkpoints at Boston Logan International Airport, we find that in situations where the uncertainty in customer arrival rates is significant, dynamically reallocating servers can substantially reduce waiting time. Moreover, we find that intuitive switching strategies that are optimal for queues with homogeneous entry rates are not optimal in this setting. Keywords: control of queues, fluid queues, approximate dynamic programming, dynamic server allocation, workforce management.
© 2011 IIE Transactions
Martonosi, Susan E. (2011, December). Dynamic Server Allocation at Parallel Queues. IIE Transactions, 43(12), 863-877.