Cloud Computing Bible

Chapter 6. Capacity Planning

IN THIS CHAPTER

• Learning about capacity planning for the cloud

• Capturing baselines and metrics

• Determining resources and their ceilings

• Scaling your systems appropriately

Capacity planning seeks to match demand to available resources. Capacity planning examines what systems are in place, measures their performance, and determines patterns in usage that enables the planner to predict demand. Resources are provisioned and allocated to meet demand.

Although capacity planning measures performance and in some cases adds to the expertise needed to improve or optimize performance, the goal of capacity planning is to accommodate the workload and not to improve efficiency. Performance tuning and optimization is not a primary goal of capacity planners.

To successfully adjust a system's capacity, you need to first understand the workload that is being satisfied and characterize that workload. A system uses resources to satisfy cloud computing demands that include processor, memory, storage, and network capacity. Each of these resources has a utilization rate, and one or more of these resources reaches a ceiling that limits performance when demand increases.

It is the goal of a capacity planner to identify the critical resource that has this resource ceiling and add more resources to move the bottleneck to higher levels of demand.

Scaling a system can be done by scaling up vertically to more powerful systems or by scaling out horizontally to more but less powerful systems. ...