ITIL® Capacity Management – As Easy as 1-2-3

In the ITIL guidance, Capacity Management is broken down into three related sub-processes. In this blog we will look at the three subprocesses and how they help us have better visibility into customer needs.
The first of the subprocesses is Component Capacity Management. For this subprocess we could easily substitute the word Utilization, for the purpose of this subprocess is to maximize the effective utilization of the components we have. Whether we’re discussing disk space, bandwidth, processors, memory allocations, or any other use of our physical and virtual components, the goal is to extract the most value we can from the components that we have. All of the capacity management processes have a financial management link, so here clearly the goal is to be able to defer expenditures until needed, and to balance the cost of provisioning to the resource requirements.
The second of the subprocesses is Service Capacity Management. For this subprocess we could substitute the phrase “End-to-end Performance.” The purpose here is to ensure that services have the right level of end-to end throughput and response time to meet customer requirements. Again, the goal is “enough,” enough performance to meet the need without gold-plating or what in the Lean world we would call “overprocessing,” or over-delivery (and overspending) relative to the business need.
The third subprocess is Business Capacity Management. Here would could substitute the phrase “future planning,” and there is a straight line between business capacity management and budget planning. Here we look at both the existing component and service capacity needs AND the future ones; next week, next month, next year, what is happening based on the business plan and what are the implications for the capacity plan. In short, everything in capacity management is demand-driven. Business Processes drive business activity drive consumption of service. As business use increases (demand), provisioning must scale to support it (supply). This of course has implications for budgeting and spending patterns, with the rule of thumb that we wish to plan for what is needed, and defer expenditures until the need is realized. These could be for new services, or changes in the use patterns of existing services.
Techniques used in Capacity Management include application sizing, simulation or analytical modeling, and the use of a tactical capacity plan to maintain visibility across your services. Half the point of having a process defined like this is to establish this as a focus area, where the Capacity Manager can look across technical/functional disciplines to ensure that capacity provisioning is optimized over time.
How well does your organization do capacity management? Is the focus too technical, looking at the component level in detail but perhaps missing the end-to-end? Do you have the right interactions with your business customers to get a decent forecast of future needs and patterns of use so that your planning and budgeting is properly aligned? Do you have alignment with the members of your team looking at new technologies and their implications for capacity and service improvement?