Introduction

This chapter covers logical compute design. Compute refers to the processor and memory resources required to support the virtual machines running in the vSphere environment. Calculating the required CPU and memory resources is an important part of the design process and ensures that the environment will be able to support the virtual machine workloads. Design decisions, such as scaling up, scaling out, and clustering hosts, are covered as well. The following diagram displays how the compute design is integrated into the design process:

In a physical environment where a single operating system or a single application is installed on a dedicated physical hardware, compute utilization usually averages 10-20 percent of the available resources. A majority of the memory and CPU resources are idle and wasted. In a virtual environment, the resources available are utilized by multiple operating systems and applications. It is not uncommon to see a usage of 65-80% of the available resources...