Given the continued growth of the World-Wide Web, performance of Web servers is becoming increasingly important. File caching can be used to reduce the time that it takes a Web server to respond to client requests, by storing the most popular files in the main memory of the Web server, and by reducing the volume of data that must be transferred between secondary storage and the Web server. In this paper, we use trace-driven simulation to evaluate the effects of various replacement, threshold, and partitioning policies on the performance of a Web server. The workload traces for the simulations come from Web server access logs, from six different Internet Web servers. The traces represent three different orders of magnitude in server activity and two different orders of magnitude in time duration. The results from our simulation study show that frequency-based caching strategies, using a variation of the LFU (Least Frequently Used) replacement policy, perform the best for the Web server ...

The phenomenal growth in popularity of the World-Wide Web (WWW or "the Web") has made WWW traffic the fastest growing component of network packet and byte traffic on the NSFNET backbone. This growth has triggered much recent research activity aimed at improving Web performance and scalability: reducing the volume of network traffic produced by Web clients and servers by using file/document caching, and reducing the latency for WWW users by using improved protocols for Web interaction. Fundamental to the goal of improving WWW performance is an understanding of WWW workloads. This thesis presents a workload characterization study for World-Wide Web servers. Six different data sets are used in this study: three from academic (i.e., university) environments, two from scientific research organizations, and one from a commercial Internet provider. These data sets represent three different orders of magnitude in server activity, and two different orders of magnitude in time duration, ranging...