A distributed system reference architecture for adaptive QoS and resource management

Abstract

This paper deals with large, distributed real-time systems that have execution times and resource utilizations which cannot be characterized a priori. (The motivation for our work is provided in part by the characteristics of combat systems.) There are several implications of these characteristics: 1) demand space workload characterizations may need to be determined a posteriori, and 2) an adaptive approach to resource allocation may be necessary to accommodate dynamic workload changes. Thus, we present a scheme for dynamically managing distributed computing resources by continuously computing and assessing QoS and resource utilization metrics that are determined a posteriori. Specifically, the paper presents an adaptive distributed system reference architecture that is suitable for such an approach. This reference architecture provides the capabilities and infrastructure needed to construct multi-component, replicated, distributed object real-time systems that negotiate for a given level of QoS from the underlying distributed computing resources.