A Hybrid Caching Strategy for Streaming Media Files

A recently proposed streaming media file caching algorithm, called Resource Based Caching (RBC), considers the impact of both file size and required delivery bandwidth in making cache insertion and replacement decisions. Previous comparisons between RBC and the least-frequency-used (LFU) policy conclude that RBC provides a better byte hit ratio in the cache. This paper revisits this policy comparison over a much broader region of the system design space than previously considered. The results provide more complete insight into the behavior of RBC, and support new conclusions about the relative performance of RBC and LFU. A new policy, Pooled RBC, is proposed. Pooled RBC includes three improvements to the original RBC policy and has significantly better performance than RBC. Finally, a new hybrid LFU/interval caching strategy is proposed. The new hybrid policy is significantly simpler to implement than RBC and performs as well or better than both Pooled RBC and LFU.