Systems with Homogeneous Workloads

In order to smoothly create the modeling knowledge in the readers, in this chapter we analyze some elementary problems that can be considered as a reference for the implementation of more complex ones. To start with simple models, we consider a load consisting of requests having similar characteristics, i.e., single class workloads. We hope that readers can gain experience step by step analyzing models of increasing complexity. It must be pointed out that even with these simple models many interesting performance problems can be addressed. Two capacity planning studies are presented for a web server and a data center, respectively. A version of the latter parameterized at system-level with service demands is also analyzed. The identification of the workload that allows a server to work in the optimal operating point concludes the chapter.