Start a job in a queue

In most cases you can debug a job by putting ddt --connect in front of the existing mpiexec or equivalent command in your job script. If a GUI is running on the login node or it is connected to it via the remote client, a message is displayed prompting you with the option to debug the job when it starts.

See Express Launch (DDT) and Reverse Connect for more details.

If Linaro DDT has been configured to be integrated with a queue/batch environment, as described in Integration with queuing systems then you can use Linaro DDT to submit your job directly from the user interface. In this case, a Submit button is displayed on the Run window, instead of a Run button. When you click Submit on the Run window the queue status is displayed until your job starts. Linaro DDT will execute the display command every second and show you the standard output. If your queue display is graphical or interactive you cannot use it here.

If your job does not start or you decide not to run it, click Cancel Job. If the regular expression you entered for getting the job id is invalid, or if an error is reported, Linaro DDT will not be able to remove your job from the queue. In this case we strongly recommend that you check the job has been removed before submitting another as it is possible for a forgotten job to execute on the cluster and either waste resources or interfere with other debug sessions.

When your job is running, it connects to Linaro DDT and you can debug it.