The Oracle Management Cloud is a very broad platform for every developer or Ops to get out all the information that is needed.

This is why this platform is an ideal one to be used in a DevOps strategy. Why? It has so many features to do analysis from both a developers perspective as an operations perspective. Combine these two and your team will act faster in detecting and solving issues, or even be pro active about possible bottlenecks in applications.

One of the zillion features, although a small one I discovered is the ability to record and dump a Java snapshot, or even better known as Java Flight Recorder Dump.

Through OMC it is possible with the help of the Diagnostic framework from Oracle WebLogic ( WLDF ) to dump a recording, or dump several recordings.

These recordings can be used to analyse the behaviour of the entire JVM - in this case the JVM of  a particular WebLogic Server Instance.

 

 

Oracle Management Cloud - Java Agent version

 

To be able to do a Java Flight recorder dump out of the OMC console, the Java APM agent must be on the 1.22 version. Older version do not have this feature implemented yet. You can see your version at:

So if you're not on this version, upgrade the APM agent to the latest versions.

 

 

 

 

 

Performing a Java Flight Recorder Dump

 

If the version matches then you can do a dump of you WebLogic Server JVM. This is how you do it:

  • Navigate form the OMC home to the APM dashboard

  • In the left pane, select Diagnostc Snapshots

 

 

 

  • Select JFR Dumps. The JFR screen appears. Click on Take JFR Dump, fill in a name or take the default name
  • Click then Select Appserver, a list with the Application Servers will be listed:

The JFR Support can be set to Yes, No or Off. No is because the version of the agent, yes or no dpends or the WebLogic Server JVM has the Commercial feature enabled in it's startup parameters. If not, add them and restart the WebLogic Server JVM

 

-XX:+UnlockCommercialFeatures -XX:+FlightRecorder

 

  • Click on


A dump will be create for analysis with the Java Flightrecorder.

 

Note - Beware that the content of your recording depends on the level on which your diagnostic volume is set on the the particular WebLogic JVM, which can be set to Low, Medium or High. You can set this per WebLogic Server in the Administration Console on the General Tab. Default it is set to Low.

 

Conclusion

 

If you are an experienced administrator, you see that it is rather easy to perform these steps, it's a nice addition in doing some deep level diagnoses with the help of the Oracle Management Cloud.