Javadump produces files that contain diagnostic information related to the JVM and a Java™ application captured at a point during execution. For example, the information can be about the operating system, the application environment, threads, stacks, locks, and memory.
By default, a Javadump occurs when the JVM terminates unexpectedly. A Javadump can also be triggered by sending specific signals to the JVM. Javadumps are human readable.
The preferred way to control the production of Javadumps is by enabling dump agents (see Using dump agents) using –Xdump:java: on application startup. You can also control Javadumps by the use of environment variables. See Environment variables and Javadump.
Default agents are in place that (if not overridden) create Javadumps when the JVM terminates unexpectedly or when an out-of-memory exception occurs. Javadumps are also triggered by default when specific signals are received by the JVM.