HP XC System 4.x Software Debugging Running Applications, Exiting TotalView, Run the application

6.2.1.7 Debugging Running Applications

As an alternative to the method described in “Debugging an Application”, it is also possible to "attach" an instance of TotalView to an application which is already running.

1.Compile a long-running application as in “Debugging an Application”: $ mpicc -g -o Psimple simple.c -lm

2.Run the application:

$ mpirun -srun -n2 Psimple

3.Start TotalView: $ totalview

4.Select Unattached in the TotalView Root Window to display a list of running processes. Double-click on the srun process to attach to it.

5.The TotalView Process Window appears, displaying information on the srun process. Select Attached in the TotalView Root Window.

6.Double-click one of the remote srun processes to display it in the TotalView Process Window.

7.Now you should be able set breakpoints to debug the application.

6.2.1.8Exiting TotalView

Make sure your job has completed before exiting TotalView. This may require that you wait a few seconds from the time your job has completed until srun has completely exited.

If you exit TotalView before your job is completed, use the squeue command to ensure that your job is not still on the system.

$ squeue

If it is still there, use the following command to remove all of your jobs:

$ scancel --user username

To cancel individual jobs, see the scancel manpage for information about selective job cancellation.

6.2 Debugging Parallel Applications 67