Planning for Workload Manager

WLM allows you to set targets for and to set limits on CPU, physical memory use, and disk I/O bandwidth for different processes and applications. This provides better control over the use of critical system resources at peak loads. PowerHA® SystemMirror® allows you to configure WLM classes into PowerHA SystemMirror resource groups so that the starting and stopping of WLM and the active WLM configuration can be under cluster control.

PowerHA SystemMirror does not verify every aspect of your WLM configuration; therefore, it is your responsibility to ensure the integrity of the WLM configuration files. After you add the WLM classes to a PowerHA SystemMirror resource group, the verification utility checks only whether the required WLM classes exist. Therefore, you must understand how WLM works and configure it carefully. Incorrect but acceptable configuration parameters can impede the productivity and availability of your system.

For complete information on how to set up and use Workload Manager, see the IBM AIX Workload Manager (WLM) Redbooks® publication.

Workload Manager distributes system resources among processes that request them according to the class they are in. Processes are assigned to specific classes according to class assignment rules. Planning for WLM integration with PowerHA SystemMirror includes two basic steps:

1. Using AIX SMIT panels to define the WLM classes and class assignment rules related to highly available applications.
2. Using PowerHA SystemMirror SMIT panels to establish the association between the WLM configuration and the PowerHA SystemMirror resource groups.