[AIX Solaris HP-UX Linux Windows]

Tuning HotSpot Java virtual machines (Solaris & HP-UX)

The architecture of the Sun-developed, HP-ported HotSpot Java™ virtual machine (JVM) has evolved differently than the IBM-developed software development kit (SDK.) Its internal structure, for young or old generation and permanent regions, arises to primarily support generational garbage collection, as well as other garbage collection modes as necessary.

Before you begin

Note: This topic references one or more of the application server log files. As a recommended alternative, you can configure the server to use the High Performance Extensible Logging (HPEL) log and trace infrastructure instead of using SystemOut.log , SystemErr.log, trace.log, and activity.log files on distributed and IBM® i systems. You can also use HPEL in conjunction with your native z/OS® logging facilities. If you are using HPEL, you can access all of your log and trace information using the LogViewer command-line tool from your server profile bin directory. See the information about using HPEL to troubleshoot applications for more information on using HPEL.
  • Determine the type of JVM on which your application server is running.

    Issue the java –fullversion command from within your application server app_server_root/java/bin directory. In response to this command, the application server writes information about the JVM, including the JVM provider information, into the SystemOut.log file. If your application server is running on an IBM virtual machine for Java, see the topicTuning the IBM virtual machine for Java.

  • Verify that the following statements are true for your system:
    1. The most recent supported version of the JVM is installed on your system.
    2. The most recent service update is installed on your system. Almost every new service level includes JVM performance improvements.

About this task

Tuning the Sun HotSpot JVM is an iterative process where the JVM configuration is developed, data gathered, primarily from verbosegc data, and then analyzed, and any configuration revisions applied on the next cycle. Perform one or more of the following steps if you need to tune your Sun HotSpot JVM.

Procedure

What to do next

Gather and analyze data to evaluate the configuration, typically using verbosegc. Continue to gather and analyze data as you make tuning changes until you are satisfied with how the JVM is performing.


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Timestamp icon Last updated: March 5, 2017 17:28
File name: tprf_hotspot_jvm.html