Thread-Width Stepping

When TotalView executes a thread-width stepping command, it steps the TOI while holding the other threads in the process.

Note:   Thread stepping is not implemented on Sun platforms. On SGI platforms, thread stepping is not available with pthread programs. If, however, your program is based on SGI compiler-generated parallelism such as used in OpenMP, thread stepping is available.

Stepping a thread tells TotalView that it should just run that thread. TotalView also allows all manager threads to run freely while it steps the TOI.

Thread-level single-step operations can fail to complete if the TOI needs to synchronize with a thread that is not running. For example, if the TOI requires a lock that another held thread owns, and steps over a call that tries to acquire the lock, the primary thread cannot continue successfully. You must allow the other thread to run in order to release the lock. If this applies, you should instead use process width.