一种共享存储视频服务器集群的请求调度策略  

Request Scheduling Strategy for Shared Storage Based Video Media Server Cluster

作　　者：刘侃[1] 李俊[1] 杨坚[1] 

机构地区：[1]中国科学技术大学自动化系网络传播系统与控制联合实验室,安徽合肥230027

出　　处：《小型微型计算机系统》2009年第4期666-670,共5页Journal of Chinese Computer Systems

基　　金：中国科学院院长奖获得者科研启动专项基金项目(2006AA01Z114)资助

摘　　要：在VOD服务器集群中,对用户服务请求的合理调度是提高集群整体性能的关键技术之一.本文针对共享存储结构下的服务器机群,在请求调度算法LoadCache_rep基础上进行改进,提出一种基于视频节目点播集中度的调度策略,该策略通过将相近的点播请求调度至相同服务器上以充分利用服务器的缓存机制,同时兼顾均衡各服务器间的负载.并根据实时负载变化对请求进行迁移以消除VCR操作对负载分布的影响.仿真试验表明,该策略能有效提高视频服务器集群的运行性能.In clustered VOD （Video-on-Demand） server system, request scheduling is one of the most important techniques to improve performance of server cluster. In this paper a request concentricity degree （CD） based scheduling algorithm improved from algorithm LoadCache-rep is proposed for the shared storage based server cluster. The strategy aims to schedule similar requests to the same server to make full use of caching capacity on the media server and also balance the load between servers. Request migration strategy is also used to rebalance the potential load imbalance caused by some VCR operations. Experiment showed the algorithm improved performance effectively.

关 键 词：视频点播 共享存储 请求调度 负载均衡 动态迁移 

分 类 号：TP331[自动化与计算机技术—计算机系统结构]