Chapter 4. Tools for determining performance problems 99
Job report
Pool report
Resource report
If you collect the trace data, you may also produce more detailed reports:
Transaction report
Lock report
Batch job trace report
Advisor
Advisor is a semi-automatic tuner that provides an easy-to-use way to improve many of the
performance characteristics of your system. It can help you to define specific tuning values
and other parts of a processing environment to provide better performance for specific
processing conditions on your system.
Advisor analyzes performance data and then produces recommendations and conclusions to
help improve performance. It may recommend changes to basic system tuning values and list
conclusions about conditions that can cause performance problems.
You can choose to have the advisor change system tuning values as it recommends, or you
can decide to make only the changes you select. You can use Advisor’s conclusions to:
Make changes to your system
Guide further performance data collection
Help you request performance reports that contain more information and explanations
Advisor may help you to improve system performance, but it does not identify or correct all
performance problems for you. Performance information analyzed by Advisor includes:
Storage pool sizes
Activity levels
Disk and CPU utilization
Communications utilizations and error rates
I/O processor (IOP) utilization
Unusual job activities: Exceptions or excessive use of system resources
Interactive trace data (when available)
Advisor does not:
Make any recommendations for changing specific application programs to improve their
performance
Analyze non-interactive trace data
4.3.4 Using the system performance tools
If you suspect your system requires tuning changes, you need to investigate the items
outlined in this section.
CPU utilization
Java and WebSphere Application Server applications are typically CPU-intensive. Therefore,
you must first check CPU utilization. Use the following commands to determine if there are
too many jobs on the system or if some jobs are using a large percentage of processor time:
WRKACTJOB (See the examples in 4.2.3, “WRKACTJOB command” on page 31.)
WRKSYSACT

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