VOD服务器集群上的副本存储调度策略

摘要

Replicated files' storing and scheduling policy is a critical factor that impacts the serving capability of clustered VOD ( VideoOn-Demand) server systems.This paper brings forward an Erlang-B formula based algorithm of replicated file storing and scheduling, which is based on taking the variables into account comprehensively such as video popularity, session length and video' s bitrate, etc.Simulation test shows that this algorithm can enable clustered servers provide satisfactory service performances by lowering request rejection rate and making the request rejection rate distribute more balanced among different videos.%VOD服务器集群中,副本放置及调度策略是影响服务质量的关键因素之一.综合考虑视频的热度、会话长度以及视频码率等变量,提出了一种基于Erlang-B公式的副本放置以及调度算法.仿真试验表明,该算法降低了请求拒绝率,同时也使请求拒绝率在不同视频之间分布得更加均衡,可使服务器集群提供较优的服务质量.