Java Analysis

Linux Applications - Best Practices - Java

ESAMON screens/ESAMAP reports:

  • Java Virtual Machines
  • JVM Threads
  • Using zVPS to find information for solving issues with the Linux applications:


    ESAJVM - Shows information about the Java Virtual Machine on nodes being monitored.

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  • Node - This shows the zTCP node name.
  • Name - This shows the name of the JVM application as defined in snmpd.conf.
  • Type - This shows the type of application as defined in the snmpd.conf.
  • CPU (ms) - This shows the total CPU for all the java threads for this server.
  • Heap Memory (MB) - This shows the total amount of JVM heap memory - Initially requested, Used, Committed and Maximum for all heap memory pools.

  • Note: Can click on a line (zview) or zoom (z/VM) to see all of the JVM threads (ESAJVMT).
    ESAJVMT - Shows information about the Java Virtual Machine threads.

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  • Node - This shows the name of the server.
  • Application Name - This shows the description of the JVM application as defined in snmpd.conf.
  • Thrd Num - This shows the thread number.
  • Blocks - This shows the rate per second that the thread has blocked to enter or re-enter a monitor.
  • Wait - This shows the rate per second that the thread has waited for notification.
  • CPU (ms) - This shows the CPU time used by the thread.
  • Status - This shows the status of the thread.
  •   Blocked - A blocked thread is a thread in a runnable state of the thread life cycle and is contending for a lock.
    A blocked thread has more impact to the scheduler.
  •   New Thread- a not yet started thread
  •   Runnable- executing in the JVM but may be waiting for other resources such as CPU.
  •   Terminated- a thread that has completed execution.
  •   Timed wait- waiting a specific amount of time.
  •   Waiting -A thread in wait state is dormant and has less impact on the scheduler.
  •   Second status - In native- executing native code via Java Native Interface (JNI)
  •   Second status - Suspended- suspended via a Thread.suspend() call.
  • Thread Name - This shows the name of the thread.

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