Performance enhancement using intra-server caching in a continuous media server

Abstract

Continuity of stream playback is the crucial constraint in designing a continuous media server. From a distributed memory architectural model developed earlier, we found that there were many points where the stream capacity of the server could be improved. The stream capacity was usually limited by the storage bottlenecks. Serving streams from memory cache eliminates disk accesses and data transfers between nodes which, in turn, helps relieve those bottlenecks. However, the capacity of the server ultimately depends on client access patterns. Client request assignment has an impact on cache hit ratio as well as workload distribution. It is also the major factor reflecting the server performance. In some cases where lower playback quality at some point in time is acceptable, delays can be added to improve the missed packet rate. This paper proposes various techniques to enhance the server performance and shows their reflections under different circumstances. Some techniques work well together. The best combination improves the capacity of the server by approximately 30%.