WLM Component of CPExpert


In 1994, IBM began delivering the Workload Manager as a part of the new MVS/ESA SP5.1 operating system release.  The Workload Manager provides a radical departure from earlier IBM operating system software. With the Workload Manager, users no longer provide detailed instructions to the System Resources Manager about how to process work. Instead, users partition their workload into service classes, and specify performance goals for each service class.

In 1995, the WLM Component of CPExpert was introduced, to analyze performance aspects of MVS environments running under IBM’s Workload Manager.

The WLM Component analyzes data recorded in standard SMF records (and placed into a performance data base, by MXG® or CA-MICS ). The SMF data is analyzed to:

Detect problems with your Workload Manager Service Definition.
Analyze how well the Workload Manager meets performance goals.
Identify the reasons performance goals were not achieved.
Suggest alternatives you can implement to improve performance.

The WLM Component also evaluates overall system areas:

The WLM Component analyzes your PR/SM, IRD, and HiperDispatch environment to identify potential performance problems with PR/SM definitions and LPAR performance.

The WLM Component analyzes your coupling facility and XCF parameters and system configuration, and suggests ways to improve the performance of your parallel sysplex.
 
The WLM Component analyzes your paging subsystem, and suggests changes to improve system performance.
 
The WLM Component analyzes System Logger, to identify performance problems that often cause significant system overhead.

 
The WLM Component analyzes your WLM-managed initiators, to identify performance problems with service class,  job, and job class specifications..

 
The WLM Component analyzes your performance aspects of the zSeries Application Assist Processor (zAAP), to identify performance problems and the causes of poor performance with zAAP processors..

 
The WLM Component analyzes your performance aspects of the System z9 Integrated Information Processor (zIIP), to identify performance problems and the causes of poor performance with zIIP processors.
 
The WLM Component analyzes Resource Enqueue information, to identify resource contention problems.

The WLM Component analyzes queuing for processor resources, to identify processor contention problems.
 
The WLM Component analyzes CPU Measurement Facility (SMF Type 113) information, to identify excessive CPU penalty cycle problems.

The WLM Component is normally executed each day, as a final step in the daily update of your performance data base. 

For those performance analysts who have a good grasp of Workload Manager concepts, constraints, and analysis techniques, the WLM Component can significantly reduce the time required to perform daily analysis of system performance.

Since only problem situations are reported by the WLM Component, performance analysts can focus on problems and not waste time analyzing nonproductive areas.

Users typically find that a number of problems are initially identified by CPExpert. These problems usually are resolved within a fairly short time. If the problems cannot be resolved (for example, because of "political" realities), the guidance provided to CPExpert usually is changed.

The result is that during normal day-to-day operation, the WLM Component should provide an indication of a problem only if the problem is "new" - that is, the system or workload changes and a new problem is encountered or has a more significant impact on the performance of service classes.

The WLM Component User Manual provides a detailed description of each finding, and suggests alternative ways to correct the potential problem. The User Manual provides comprehensive documentation about Workload Manager concepts, algorithms, and operational features.

CPExpert is continually enhanced, with updates every 6 months. These updates provide support for new releases of IBM operating systems and provide additional analysis of performance problems.

 

Sample output from the WLM Component.

Sample "rule" description from the WLM Component User Manual.
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Last updated by Don Deese on 03/26/13.