A JITTERLESS TASKS SCHEDULING ALGORITHM FOR DISTRIBUTED MULTIMEDIA SYSTEMS
Zhang Zhan · Chinese Journal of Computers · 1999
The algorithm of resource management and allocation is very important to guarantee the application's quality of service (QoS) in distributed multimedia systems. In resource management, the QoS negotiation and admission depend on scheduling algorithm. Thus it is the kernel of resource management. Early deadline first (EDF) and rate monotonic (RM) in real time systems have been used in distributed multimedia systems today. But they can result to schedule with much jitter. Recently, a new pinwheel scheduling DSr that is little jitter scheduling is presented. But it is only suitable for uniprocessor systems. Although DSr is a distributed scheduling algorithm, its assumption is not very suitable for distributed systems so that it can not be adopted. This paper presents a jitterless integrated task scheduling algorithm DMSr that removes candidates step by step based on the pinwheel model of distance constraints. It discusses the time complexity and proves the schedulability condition. It can guarantee the QoS of multimedia tasks. Specially it can schedule with jitterless. Two examples illustrate scheduling algorithm procession and tight schedulability condition in this paper. Finally, the authors do experiments with client/server model in 100M switching Ethernet and make the compression about results in delay, jitter and CPU utilization among EDF, RM and DMSr.