Modeling and simulation of performance analysis for a cluster-based Web server

Higher scalability and availability of Web servers are required as the traffic on the Internet has been increasing dramatically over the last few years. This paper focuses on modeling and simulation of the performance analysis for the test system of a cluster-based Web server consisting of five real servers. Three ways of load balancing are introduced, namely, network address translation, IP tunneling and direct routing. Calculation of packet delay is discussed for each part of the running system according to the transferred data in the system. The input model and the system model to measure and simulate the system performance are derived, and the probability distributions of the delay data are specified for using random inputs in the model according to the Q–Q plot and the cumulative distribution function. After the solution of performance tuning problems is evaluated, the maximum process capability of the system is found and a possible performance bottleneck is analyzed.