ABSTRACT

The rapid growth in use of the World Wide Web requires deployment of powerful servers running Hyper Text Transfer Protocol (HTTP) for publishing information. The growing client base on the Internet will increase the load on Web servers. In addition, dynamic content generation and proxy accesses to database backend will increase the demands on Web servers. Performance evaluation of various implementations of the service is of great importance. It is essential to analyze and evaluate the capacity limits of various servers. This will help server administrators with capacity planning and deploying suitable servers to meet their needs. The Web Capacity Analysis Tool (WCAT) is a simple and extendible tool for Web server capacity analysis. The Web Capacity Analysis Tool provides a framework of tools consisting of a controller and client software which help in measuring the performance of Web servers in architecture and system-independent manner. This paper discusses the architecture of the Web Capacity Analysis Tool, its workload mix, evaluation configurations, methodology, and method of reporting results. The Web Capacity Analysis Tool has the flexibility to evolve with the evolution in Web servers and server add-on components.

Introduction

The Internet is comprised of a loosely connected web of computers, each with the ability to publish and receive information. HTTP provides a way to publish information in documents containing hypertext links. The richness of connections and content offered via HTTP spurs the growth of Internet traffic. The traffic on the Internet—and demands on servers—is increasing day by day. In the past, HTTP servers were used primarily in the education market. Currently, commercial organizations are installing servers both on the Internet and intranets. Appropriate choice of platforms for hardware and software depend on performance of various systems. A consistent and reliable set of tools for evaluating capacity of these servers is essential for both designers and administrators alike. A good set of tools for evaluating Web servers is required. The tool should be easy to deploy and should provide the means and flexibility to evaluate performance. Results from the tool could be used in evaluation, analysis, and development. Web Capacity Analysis Tool supports extendible workload configurations and evaluation criteria and immensely simplifies capacity analysis. In this paper, we present the requirements, architecture, workload mix, and methodology of the Web Capacity Analysis Tool.