Customizing Application Performance Analyzer for use with J9VM

This chapter describes the tasks for configuring Java™ support. Sampling a Java application requires loading a JVMTI agent to obtain Java samples. There are two ways that this can be accomplished:
  • Use a preloaded JVMTI agent. This is the recommended option.

    This option loads the JVMTI agent when the target Java job is started. The agent remains alive until the Java job terminates. The agent sits in a wait state until a sampling session is requested. After the sampling session completes, the agent returns to a wait state.

  • Use a dynamically loaded JVMTI agent.

    This option loads the JVMTI agent at the time that a sampling session is started. The JVMTI agent is loaded using the Java Attach API. The agent runs only for the duration of the sampling session.

Application Performance Analyzer can be configured to support one or the other of these options, not both.
Work closely with a security administrator and a USS administrator to complete the following tasks:
  1. Install USS files in an Application Performance Analyzer directory on your system
  2. Provide APF authorization for the Application Performance Analyzer USS files
  3. Assign USS permissions to the Application Performance Analyzer started task
  4. Set up Security Access Rules
  5. Update the started task configuration settings
  6. Enable Java attach API (for a dynamically loaded JVMTI agent) or Specify a preloaded JVMTI agent

Application Performance Analyzer can be configured to support either 31-bit or 64-bit Java in the started task. Regardless of how it is configured, Application Performance Analyzer can sample both 31-bit Java applications and 64-bit Java applications, with the appropriate Java PTFs installed on your system.