The new JRockit Flight Recorder has some very interesting properties. It can be used like the black box of an airplane, allowing users to go back in time and check what was happening around the time when something went wrong. Here is how to enable the default continuous recording in JRockit to allow for that use case.

The flight recorder is on by default in JRockit R28, the problem is that there is no recording running by default. To configure JRockit to start with the default recording running, add the parameter:

-XX:FlightRecorderOptions=defaultrecording=true

That will enable a recording with recording ID 0. You can see that it has been started properly by choosing Show Recordings from the context menu in JRockit Mission Control.

You should see something similar to the picture below.

Simply right click on the recording and select dump to dump information available in the flight recorder. You can select to dump data for a specific period of time or all data.

For more information about the command line parameters available to control the Flight Recorder, see the JRockit documentation.