Determine when and how to expand your system

As your business needs change, your system must also change. To prepare for any changes, you will want to model the current system and then see what would happen if the system, the configuration, or the workload were changed.

As your business needs evolve, so do your system needs. To plan for future system needs and growth, you will need to determine what would happen if the system, the configuration, or the workload were changed. This process is called trend analysis and should be done monthly. As your system approaches resource capacity guidelines, you may want to gather this data more frequently.

Trend analysis should be done separately for interactive and batch environments. If your company uses a certain application extensively, you may want to perform a trend analysis for the application. Another environment that may be important to track would be the end-of-month processing. It is important that you collect trend analysis data consistently. If your system's peak workload hours are between 10:00 AM and 2:00 PM and you collect trend analysis data for this time period, do not compare this data to data collected from other time periods.

To do a proper job of capacity planning and performance analysis, you must collect, analyze, maintain, and archive performance data. IBM® offers several tools that help you with your capacity planning, resource estimating, and sizing:

IBM Performance Management for eServer™ iSeries™
PM iSeries completely automates collecting data, analyzing data, and archiving data and provides you with summarized performance and capacity information that is easy to understand. PM iSeries helps you plan for and manage system resources through ongoing analysis of key performance indicators. This function ships with the i5/OS™ licensed program. There is nothing that you need to do other than activate the function and periodically check that the data is being collected and transmitted to IBM. All collection sites are network secure, and the PM iSeries service transmits only nonproprietary performance data to IBM. The time of the transfer is completely under your control.
Workload Estimator
The Workload Estimator is a tool that helps you size your system needs based on estimated workloads for specific workload types. Through a web-based application, you can size the upgrade to the required iSeries system that accommodates your existing system's utilization, performance, and growth as reported by PM iSeries. As an additional option, sizings can also include capacity for adding specific applications like Domino®, Java™, and WebSphere®, or the consolidation of multiple workloads on one system. This capability allows you to plan for future system requirements based on existing utilization data coming from your own system.
PATROL for iSeries - Predict
This product helps manage iSeries performance by automating many of the routine administration tasks required for high availability and optimal performance. Additionally, it offers detailed capacity planning information to help you plan the growth of your iSeries environment.

See Select a performance management strategy for more information about creating and implementing a performance strategy.

Related concepts
IBM Performance Management for eServer iSeries
Workload Estimator for iSeries
PATROL for iSeries (AS/400) - Predict
Related reference
Select a performance management strategy