Dynamic RePacking: A Content Replication Policy for Clustered Multimedia Servers

Dynamic replication is a technique that can be used by clustered multimedia servers to evaluate the demand for individual streams and selectively replicate or move content to facilitate load balancing. In this paper we explain the motivation for using dynamic replication and provide a brief description of some existing dynamic replication policies. We present a new policy called Dynamic RePacking. This policy is based on the existing MMPacking algorithm [11], but has been modified to handle nodes and files with varying bandwidth and storage characteristics and to reduce the cost of adapting to changes in client demand or server configuration. Simulation results show that Dynamic RePacking performs better than both the original MMPacking algorithm and the threshold-based scheme which we have simulated for comparison. Our results also show that Dynamic RePacking performs significantly less movement and replication of files than the original MMPacking algorithm.