| Multimedia applications have inherent real-time requirements and large processing and communication demands. Designing a multimedia system that copes with these demands has been a challenging problem, and thus a significant amount of effort has been devoted to provide solutions for better performance. Efficient resource management is a way of overcoming this challenge. It offers Quality of Service (QoS) to as many clients as possible by intelligently administering and scheduling the limited system resources. The objective of this thesis is to design and analyze resource management techniques for multimedia systems, focusing on the following important resource management aspects: resource sharing, admission control, and resource scheduling.; First, an analytical model of a resource sharing scheme called interval caching is developed for non-interactive video servers. The model has been extensively validated over a range of client requests, video data, and server parameters. Using this model, the impact of different parameters has been studied on the performance of the interval caching scheme. Second, an analytical model of interval caching for interactive video servers is developed. The model captures the interactions of various VCR functionalities such as fast-forward, rewind, and pause, and predicts the improvement in system throughput due to interval caching. Using this model as a design tool, the impact of different VCR operations on client requests, rejection probability, the effect of cache size, and server design alternatives with cost constraints have been analyzed. Third, a statistical admission control policy is developed for interval caching. The admission control strategy is designed to augment possible performance gains due to interval caching. The strategy attempts to keep the disk and cache utilization as high as possible while reserving a certain amount of disk bandwidth for streams that are evicted from the cache and are likely to cause jitter. Finally, we develop an end-to-end resource scheduling scheme to support the presentation of composite multimedia information in a networked environment. The scheme provides an efficient way of scheduling resources node-by-node in a network path, and also attempts to maximize per-node throughput, which eventually results in high throughput in the entire distributed system. |
