Batching and dynamic allocation techniques for increasing the stream capacity of an on-demand media server

A server for an interactive distributed multimedia system may require thousands of gigabytes of storage space and high I/O bandwidth. In order to maximize system utilization, and thus minimize cost, the load must be balanced among the server's disks, interconnection network and scheduler. Many algorithms for maximizing retrieval capacity from the storage system have been proposed. This paper presents techniques for improving server capacity by assigning media requests to the nodes of a server so as to balance the load on the interconnection network and the scheduling nodes. Five policies for dynamic request assignment are developed. An important factor that affects data retrieval in a high-performance continuous media server is the degree of parallelism of data retrieval. The performance of the dynamic policies on an implementation of a server model developed earlier is presented for two values of the degree of parallelism.