Performance Management

The Performance Explorer is a data collection and reporting tool that helps performance analysts identify the cause of performance problems that cannot be identified by other tools in the i5/OS operating system or by most of the reporting facilities in the Performance Tools for System i product. The collection function in the Performance Explorer is included in the i5/OS operating system. The reporting function is a special advanced type of performance report that is available only through the Performance Tools for System i licensed product. Two reasons to use Performance Explorer are:

• Isolating performance problems to the system resource, application, program, procedure, or method that is causing the problem.
• Analyzing the performance of individual applications or key middleware components such as application servers or database servers.

The most detailed mode is called *TRACE which gathers a historical trace of performance activity for one or more jobs on the system. It provides a way to trace various activities called events that occur when applications are running or system resources are being used. Common trace events include:

• Program and procedure calls and returns.
• Storage allocations and de-allocations.
• Disk read and write operations.
• Java method entry and exit.
• Java object creates and garbage collection activities.
• Journal operations such as start commit and end commit.
• Synchronization activities such as locks and semaphores.
• Communication events at the TCP, IP, and UDP layers.