Getting a dump from a hung JVM

On Windows, you can force the JVM to produce a Java™ dump. Alternatively, you can produce a Java dump using Windows utilities.

You can force the JVM to produce a Java dump in response to a SIGBREAK signal, which can be sent by using the Ctrl-Break key combination. You can also configure the JVM to produce a system dump on SIGBREAK by using the -Xdump:system:events=user option. See Using dump agents for details.

On Windows 7 and Windows Server 2008, you can obtain a system dump by using the Windows Task Manager.
  1. Start the Windows Task Manager.
  2. Select either the Applications or the Processes tab.
  3. Right-click the application or process, then select the Create Dump File option.

On earlier versions of Windows, you can use the User Mode Process Dumper utility, which is available as a download from www.microsoft.com. Documentation is provided with the utility. Basic usage is as follows:

userdump -p
Lists all the processes and their process IDs.
userdump xxx
Creates a dump file of a process that has a process ID of xxx. A file named processname.dmp is created in the directory where userdump.exe is run.

You can use the dump viewer to examine the system dump produced by the JVM or by the Windows utilities. For more information, see Using the dump viewer.