If you run one of the processes or threads in a group and it hits a barrier point, the Root Window displays Stopped in the Process State column for that process’s or thread’s entry, and the main Process Window displays Held in the title bar.

If you create a barrier and all the process’s threads are already at that location, TotalView won’t hold any of them. However, if you create a barrier and all of the processes and threads are not at that location, TotalView holds any thread that is already there.