A request distribution method for clustered VOD servers considering buffer sharing effects

Abstract

The clustering of multiple video servers is a popular architecture for huge VOD systems. In a clustered VOD system, user requests are distributed among the video servers by the dispatcher. Each video server consists of independent disks and a local buffer memory. The buffer mechanism is recognized helpful to the improvement of the disk performance. However, its effects have not been effectively utilized so far for the request distribution strategies of the clustered VOD system. In this work, we investigate the effects of buffer sharing on the throughput of the clustered VOD system. And, based on the results, we propose a request distribution method for the clustered VOD system, where the buffer sharing effects are utilized for improving the system's throughput. By experiments, we evaluate the performance of the proposed method compared with the conventional request distribution methods. (C) 2007 Elsevier B.V. All rights reserved.