How to create a thread dump for the J2EE Engine 6.40

A throwing object hands over the exceptions to the calling object which in turn hands the exceptions to its calling object and so on. When as thread dump is triggered, this information is written to a file. The thread dump or stack trace can help troubleshoot problems such as a hanging java server node as it shows what method was running at the time.

To trigger a java thread dump
  1. Call jcmon "/usr/sap/<SID>/<Instance>/j2ee/os_libs/jcmon pf=<path to profile file>"
  2. Choose Local Administration Menue by entering 20
  3. Choose "Dump stacktrace" by entering 10
  4. Select the Java node for which trhead dump should be triggered (see column idx and enter the corresponding number)
  5. Confirm with y
The thread dump is written to /usr/sap/<SID>/<Instance>/work/std_server<n>.out or /usr/sap/<SID>/<Instance>/j2ee/cluster/server<n> if you have triggered the stack trace for server<n>

You can also triger the stack trace using kill -3 <PID of jlaunch process>

Analyzing thread dumps

You can download the thread dump viewer from SAP SMP.
The tdv works for 640 and above and reads thread dumps for SAP/Sun(Oracle)/HP/IBM JVMs for AIX/Linux.


For 640/700 double-click on the jar file and open the thread dumps. For 710, open the thread dump viewer with the following command:
java -jar tdv.jar -version 710

Comments

  1. bloggerVAugust 31, 2011 at 10:12 PM

    Edit: You can also download the thread sump viewer from source forge http://sourceforge.net/projects/tdv/

    ReplyDelete
  2. AnonymousOctober 28, 2011 at 10:52 PM

    very helpful..keep posting

    ReplyDelete

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