Performance objectives

Establishing performance objectives can help you make good choices as you work with Db2. Although performance objectives vary for every business, how your site defines good Db2 performance depends on data processing needs and priorities.

In all cases, performance objectives must be realistic, understandable, and measurable. Typical objectives include values for:

• Acceptable response time (a duration within which some percentage of all applications have completed)
• Average throughput (the total number of transactions or queries that complete within a given time)
• System availability, including mean time to failure and the durations of downtimes

Objectives such as these define the workload for the system and determine the requirements for resources, which include processor speed, amount of storage, additional software, and so on.

For example, an objective might be that 90% of all response times on a local network during a prime shift are under 2 seconds. Another objective might be that the average response time does not exceed 6 seconds, even during peak periods. (For remote networks, response times are substantially higher.)

Often, though, available resources limit the maximum acceptable workload, which requires that you revise the objectives.