IBM 890, 870, 835 manual Tools, Workload Estimator, PM/400 Management Central

Tools

There are several tools that can be used to help project which model/processor is appropriate for an initial installation and for projecting when standby processors should be activated. The Workload Estimator is typically used for sizing an initial installation. PATROL is a capacity planner that can often be used for both initial planning and upgrade planning. PM/400 is a trending tool that helps predict growth across workloads. Management Central is a monitoring tool that can be used to identify workload growth. In addition, IBM offers a variety of service options to assist with capacity planning tasks.

Workload Estimator

The Workload Estimator supports models with CUoD. However, only the performance capacity for startup processors will be represented. Capacity for standby processors is not represented in the tool. This tool is designed for initial sizing estimates and is not intended to achieve single-processor granularity with its estimates. When the Workload Estimator “recommends” a server as having sufficient capacity to contain a set of workloads, it includes a pull-down list of other supported servers that have at least the same capacity as the recommended server.

The Workload Estimator and associated on-line documentation can be found at:

http://www.ibm.com/eserver/iseries/support/estimator

PM/400

For more detailed information about PM/400e, visit their website at http://www.ibm.com/eserver/iseries/pm400

Management Central

Use of Management Central to aid in Capacity Planning and point out where an activation of standby processors should be considered can be illustrated in the following example:

Consider the model 840-2416 with eight startup processors and four standby processors. The maximum CPU utilization attainable would be 8/12 or approximately 67%. Typical thresholds for system CPU monitoring would be 70% and 90% of total capacity. Sustained usage above 70% is an indicator that additional capacity should be considered. Usage above 90% indicates the system is reaching its capacity maximum.

Applying the above thresholds to the Model 840 with one of these Processor Features (FC 2416, 2417, or 2419) would yield thresholds of 47% and 60% respectively. These values can be seen in the following Management Central Monitor example.

When the initial threshold is reached, assuming the tool has been set up correctly, the line graph goes red indicating that additional processors may be needed. In addition, a message can be triggered and logged when the thresholds are reached, so that an accounting can be done over time of how often the thresholds are crossed. If it reaches the

final threshold value often, an upgrade should definitely be considered.

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12/15/2003