An Admission Control Scheme for Continuous Media Servers Using Caching

In continuous media servers, disk load can be reduced by using buffer cache. In order to utilize the saved disk bandwidth by caching, a continuous media server must employ an admission control scheme to decide whether a new client can be admitted for service without violating the requirements of clients already being serviced. Since deterministic admission control is based on the worst case assumption, it causes the wastage of the system resources. In this paper, we propose a statistical admission control scheme for a continuous media servers where caching is used to reduce disk load. This scheme improves disk utilization and allow more streams to be serviced with reasonable computational overhead, while maintaining near-deterministic service. The scheme, called Shortsighted Prediction Admission Control (SPAC), combines exact prediction through on-line simulation and statistical estimation using a probabilistic model of future disk load in order to reduce computation overhead.