Setting your performance objectives is an aspect of capacity management. Capacity management is the process of planning, analyzing, sizing, and optimizing capacity to satisfy demand in a timely manner and at a reasonable cost. The capacity management process has a broad scope that brings together business, service, and resource-capacity needs to deliver the level of performance required by users. For more information on capacity management, visit http://www.microsoft.com/technet/solutionaccelerators/cits/mo/smf/smfcapmg.mspx

Consider these factors when planning hardware and software performance objectives:

• Response time:The amount of time it takes for a server or an application to respond to a request.

• Throughput:The number of requests that can be served by your application for a given unit time. Throughput is frequently measured as requests or logical transactions per second. For example, how many sales lines will you process every hour? Also consider the throughput during peak usage times.

• Resource utilization:The measure of server and network resource consumption by your application. Resources include CPU, memory, disk I/O, and network I/O.

• Workload:Includes the total number of users, the concurrent active users, data volumes (I/O per second), and transaction volumes. A workload profile consists of a representative mix of clients performing various operations.

Metrics are the criteria you use to measure your business scenarios against your performance objectives. For example, you might use response time, throughput, and resource utilization as your metrics. The performance objective for each metric is the value that is acceptable to users and to your organization. You match the actual value of the metrics to your objectives to verify that you are meeting, exceeding, or failing to meet your performance objectives.