Evaluation of Tradeoffs in Resource Management Techniques for Multimedia Storage Servers

Abstract

Many modern applications can benefit from sharing of resources such as network bandwidth, disk bandwidth, and so on. In addition, many information systems store (or would like to store) data that can be of use to many different classes of applications, e.g., digital libraries type systems. Part of the difficulty in efficient resource management of such systems can then occur when these applications have vastly different performance and quality-of-service (QoS) requirements as well as resource demand characteristics. In this work we present a performance study of a multimedia storage system which serves multiple types of workloads, specifically a mixture of real-time and non-real-time workloads, by allowing sharing of resources among these different workloads while satisfying their performance requirements and QoS constraints. The broad aim of this work is to examine the issues and tradeoffs associated with mixing multiple workloads on the same server to explore the possibility of maintaining reasonable performance and QoS requirements without having to partition the resources. The main contribution of this work is the exposition of the tradeoffs involved in resource management in such systems. Although many different resources can be considered, here we concentrate mostly on the I/O bandwidth resource. The performance metrics of interest are the mean and variance of the response time for the non-real-time applications and the probability of missing a deadline for the real-time applications. The increased use of buffer space resources is also considered as a tradeoff for improvements in the above stated performance metrics, i.e., response time and probability of missing deadlines. (Also cross-referenced as UMIACS-TR-98-30)