Improving quality of service for switched processing systems

Switched processing systems (SPS) capture the essence of a fundamental resource allocation problem in many modern communication, computer and manufacturing systems involving heterogeneous processors and multiple classes of job traffic flows. Recently, increased attention has been paid to the issue of improving quality of service (QoS) performance in terms of delays and backlogs of the associated scheduling policies, rather than simply maximizing the system\´s throughput. In this study, we investigate a class of throughput maximizing scheduling policies called MaxProduct policies. The objective is that through a use of dynamically changing "optimal" queue weights, the corresponding QoS performance measure -e.g. the average system delay- can be significantly improved. The proposed approach involves a statistical smoothing technique for tracking the system\´s workload and utilizes the result of how the MaxProduct policies drain out an initially placed workload in the shortest possible time. It is further shown that the proposed modification of the MaxProduct policy, achieves maximum throughput without requiring knowledge of the incoming traffic\´s statistics. The scheduling policy is illustrated on a small SPS subject to different types of input traffic