Optical switches have been drawing attention due to their large databandwidth and low power consumption. However, scheduling policies need toaccount for the schedule reconfiguration delay of optical switches to achievegood performance. The Adaptive MaxWeight policy achieves optimal throughput forswitches with nonzero reconfiguration delay, and has been shown in simulationto have good delay performance. In this paper, we analyze the queue lengthbehavior of a switch with nonzero reconfiguration delay operating under theAdaptive MaxWeight. We first show that the Adaptive MaxWeight policy exhibits aweak state space collapse behavior in steady-state, which could be viewed as aninheritance of the MaxWeight policy in a switch with zero reconfigurationdelay. We then use the weak state space collapse result to obtain a steadystate delay bound under the Adaptive MaxWeight algorithm in heavy traffic byapplying a recently developed drift technique. The resulting delay bound isdependent on the expected schedule duration. We then derive the relationbetween the expected schedule duration and the steady state queue lengththrough drift analysis, and obtain asymptotically tight queue length bounds inthe heavy traffic regime.
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