Modeling and generating realistic streaming media server workloads

摘要

Currently, Internet hosting centers and content distribution networks leverage statistical multiplexing to meet tne performance requirements of a number of competing hosted network services. Developing efficient resource allocation mechanisms for such services requires an understanding of both the short-term and long-term behavior of client access patterns to these competing services. At the same time, streaming media services are becoming increasingly popular, presenting new challenges for designers of shared hosting services. These new challenges result from fundamentally new characteristics of streaming media relative to traditional web objects, principally different client access patterns and significantly larger computational and bandwidth overhead associated with a streaming request. To understand the characteristics of these new workloads we use two long-term traces of streaming media services to develop MediSyn, a publicly available streaming media workload generator. In summary, this paper makes the following contributions: (ⅰ) we propose a framework for modeling long-term behavior of network services by capturing the process of file introduction, non-stationary popularity of media accesses, file duration, encoding bit rate, and session duration. (ⅱ) We propose a variety of practical models based on the study of the two workloads. (ⅲ) We develop an open-source synthetic streaming service workload generator to demonstrate the capability of our framework to capture the models.