Generally capacity management is seen as a ‘good thing’. Generally it gets little attention, budget or assistance. A contradiction, but why?
We like to hide behind new terminology to go with new technology, but really the issues at heart are the same. Today’s rapid provisioning of VMs is yesterday’s CPU upgrade or additional memory – resources. Today’s hosting another 20 VMs is yesterday’s processing another million CICS transactions – workload. The key is to understand the variables in the equation and use that equation as a means of sharing understanding with the business.
The issue is usually short term issues and crises. If the building is on fire, everyone knows why you need a fire hose and using it gets priority. To handle that fire effectively though, someone needs to have thought out and answered how many fire hoses might be needed, where they need to be located, what chemicals they need to dispense for different sorts of fire and more. Unfortunately in IT, we rarely get ‘fire free’ periods when these plans can be laid down. That’s why we need capacity management separated from system administration, so the longer terms plans can be addressed without the distraction of the day to day problems.
Having a plan always helps. Things that you will need to move towards an effective capacity management capability are: -
• A clear set of objectives
• Senior management commitment
• Process/flow definition
• A realistic plan
• The right people
Key within this is having a clear idea of the service level that must be provided. This doesn’t have to be enshrined in any sort of formal Service Level Agreement, although a good SLA is of benefit to all. However, without some idea of the target, it’s difficult to know whether or not you have hit, or what you will need to do to hit that target in the future.
Essentially there is a balance between three items:
Change one and you change the others. For example, if the business wants to grow, i.e. workload will increase, either you need to change the resources to cope or the service level will degrade. Use this balance as a mechanism for talking through with the business what they want from IT. Do they want to reduce costs (fewer resources)? OK, but that means a degraded service level or less work can be processed. Do they need faster response times (better service level)? OK, but that means less work can be processed or more resources will need to be bought.
We like to hide behind new terminology to go with new technology, but really the issues at heart are the same. Today’s rapid provisioning of VMs is yesterday’s CPU upgrade or additional memory – resources. Today’s hosting another 20 VMs is yesterday’s processing another million CICS transactions – workload. The key is to understand the variables in the equation and use that equation as a means of sharing understanding with the business.
On Friday we’ll look at things that can get in the way of good capacity management.
In the meantime feel free to browse and download white papers on capacity management by joining our Metron community
Andrew Smith
Chief Sales & Marketing Officer
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