Summary

Select measures and analytic techniques to be used in managing the capacity and availability of the service system.

Description

The measures specified for managing capacity and availability can require the collection of business data, financial data, service data, technical data, service resource use data, performance data, and other data about the capacity and availability of the service system. Measurement objectives and the selection of measures and analytic techniques for capacity and availability management are largely influenced by the service agreement and specific properties of the service system.

Considerations for selection of measures also include which activities are being supported, reporting requirements, and how the information will be used. Supplier agreements should reflect or support the selected measures and analytic techniques as appropriate.

Refer to the Service Delivery (SD) (CMMI-SVC) process area for more information about establishing service agreements.


Refer to the Measurement and Analysis (MA) (CMMI-SVC) process area for more information about aligning measurement and analysis activities.


Refer to the Supplier Agreement Management (SAM) (CMMI-SVC) process area for more information about establishing supplier agreements.


 

Examples of availability measures include the following:
  • Percentage available within agreed hours (this availability can be overall service availability or service component availability)
  • Percentage unavailable within agreed hours (this unavailability can be overall service unavailability or service component unavailability)
  • Duration of downtime due to failure (typically minutes, hours, or hours per week)
  • Failure frequency
  • Scope of impact (e.g., number of users who were affected, number of minutes that users lost productivity, number of transactions or vital business functions not processed or carried out, number of application services impeded)
  • Response time of the service system to service incidents, transaction response times, and service response times (this response time can be a capacity measure or availability measure)
  • Reliability (e.g., number of service breaks, mean time between failures, mean time between service incidents)


 

Examples of capacity measures are as follows:
  • Use of service resources that are limited
  • Use of service components
  • Unused service resources that are limited
  • Unused service components
  • Throughput (e.g., number of concurrent users, number of transactions to be processed)
  • Queue length (maximum and average)
  • Number of a particular type of resource or one or more specific resources in use a selected number of times (this use can be monitored by calendar time)


Example Work Products



  1. Operational definitions of capacity and availability measures
  2. Traceability of capacity and availability measures to service requirements
  3. Tools to support collection and analysis of capacity and availability data
  4. Target measures or ranges to be met for selected measured attributes


Subpractices



1. Identify measures from organizational process assets that support capacity and availability management objectives.

2. Identify and specify additional measures that may be needed to support achieving capacity and availability management objectives for the service.

3. Analyze the relationship between identified measures and service requirements, and derive objectives that state specific target measures or ranges to be met for each measured attribute.

This analysis can provide input to the descriptions of standard services and service levels.

Refer to the Strategic Service Management (STSM) (CMMI-SVC) process area for more information about establishing standard services.