Providing resource allocation and performance isolation in a shared streaming-media hosting service

Abstract

The trend toward media content hosting is seeing a significant growth as more rich media is used in the enterprise environment and as it becomes mission critical for businesses. A shared media hosting service supports the illusion that each hosted service has its own media server, when, in reality, multiple "logical hosts" may share one physical host. For such a shared media hosting service, the ability to guarantee a specified share of server resources to a particular hosted service is very important. We present SharedMediaGuard -a shared media hosting infrastructure that can efficiently allocate the predefined shares of server resources to the hosted media services. The proposed solution is based on a unified cost function that uses a single value to reflect the combined resource requirement such as CPU, bandwidth and memory necessary to support a particular media stream depending on the stream bit rate and type of access (memory file access or disk file access). Our evaluation of SharedMediaGuard compared to the traditional, disk-based allocation strategy that assumes all content must be served from disk reveals a factor of two improvement in server throughput while providing performance isolation and QoS guarantees among the hosted services.