Effective Memory Use in a Media Server

A number of techniques have been developed for maximizing disk utilization in media servers, including disk arm scheduling and data placement ones. Instead, in this paper we focus on how to efficiently utilize the available memory. We present techniques for best memory use under different disk policies, and derive precise formulas for computing memory use. We show that with proper memory use, maximizing disk utilization does not necessarily lead to optimal throughput. In addition, we study the impact of data placement policies including disk partitioning and multiple disks. Finally, our analysis shows that maximizing disk utilization and disk striping incur high system costs, and are not advisable in a media server. 1 Introduction The storage system of a multimedia system faces more challenges than a conventional one. First, media data must be retrieved from the storage system at a specific rate --- if not, the system exhibits "jitter" or "hiccups." This timely data retrieval requirem..