Analytical and Experimental Evaluation of ClusterBased WWW Servers.pdf

Analytical and Experimental Evaluation of Cluster-Based Network Servers Enrique V. Carreray and Ricardo Bianchiniy+ y COPPE Systems Engineering + Department of Computer Science Federal University of Rio de Janeiro University of Rochester Rio de Janeiro, Brazil 21945-970 Rochester, NY 14627 fvinicio,ricardog @cos.ufrj.br University of Rochester Technical Report 718 – August 1999 Abstract tion is oblivious to the contents of the different caches. Although this caching strategy performs well when a small set of documents In this paper we use analytic modeling and simulation to evaluate accounts for a large percentage of requests and the average size of network servers implemented on clusters of workstations. More the files is small, the files serviced by network servers are becom- specifically, we model the potential benefits of locality-conscious ing larger and more numerous, especially with the proliferation of request distribution within the cluster and experimentally evaluate multimedia (image, audio, and video) files and virtual servers [7]. the performance of a cluster-based server (called L2S) we de signed Under these adverse circumstances, using the set of memorie s of in light of our experience with the model. Our most important mod- the cluster as a single large cache and distributing request s among eling results show that locality-conscious distribution on a 1