is a process used to manage information technology (IT). Its primary goal is to ensure that IT resources are right-sized to meet current and future business requirements in a cost-effective manner. One common interpretation of capacity management is described in the ITIL framework. ITIL version 3 views capacity management as comprising three sub-processes: business capacity management, service capacity management, and component
capacity management (known as resource capacity management in ITIL version 2).
As the usage of IT services change and functionality evolves, the amount of central processing units (CPUs), memory and storage to a physical or virtual
server etc. also changes. If it is possible to understand the demands being made currently, and how they will change over time, this approach proposes that capacity planning
for IT service growth becomes easier and less reactive
. If there are spikes in, for example, processing power at a particular time of the day, it proposes analyzing what is happening at that time and make changes to maximize the existing IT infrastructure, for example, tune the application, or move a batch
cycle to a quieter period. This foresight from proactive capacity planning identifies: any potential capacity related issues likely to arise and justifies any necessary investment decisions to the business and IT stakeholders i.e. the precise server requirements to accommodate a future growth in IT resource demand, a technology refresh or a data center
These activities are intended to optimize performance and efficiency, and to plan for and justify financial investments. Capacity management is concerned with:
- Monitoring the performance and throughput or load on a server, server farm, or property
- Performance analysis of measurement data, including analysis of the impact of new releases on capacity
- Performance tuning of activities to ensure the most efficient use of existing infrastructure
- Understanding the demands on the service and future plans for workload growth (or shrinkage)
- Influences on demand for computing resources
- Capacity planning of storage, computer hardware, software and connection infrastructure resources required over some future period of time.
Capacity management interacts with the discipline of Performance Engineering, both during the requirements and design activities of building a system, and when using performance monitoring as an input for managing capacity of deployed systems.