An evaluation of design trade-offs in a high-performance, media-on-demand server

We present a high-performance solution to the I/O retrieval problem in a distributed multimedia system. Parallelism of data retrieval is achieved by striping the data across multiple disks. We identify the components that contribute to media data-retrieval delay. The variable delays among these have a great bearing on the server throughput under varying load conditions. We present a buffering scheme to minimize these variations. We have implemented our model on the Intel Paragon parallel computer. The results of component-wise instrumentation of the server operation are presented and analyzed. Experimental results that demonstrate the efficacy of the buffering scheme are presented. Based on our experiments, a dynamic admission-control policy that takes server workloads into account is proposed.