Hi, This is Alex Zahdeh, one of the debugger tools developers at Cray. I had a question about how Intel MPI handles synchronization according to the MPIR debugging standard. The usual procedure for our debugger is to launch tool daemons to attach to the backend application processes while the application launcher is held at MPIR_Breakpoint. At this point the application process must be in some sort of barrier so the debugger tries to return the user to their own code by setting breakpoints at various initialization symbols for different parallel models, continuing, hitting one of the breakpoints, deleting the rest and finishing the current function. This works if the application is held before the breakpoints we set which does not seem to be the case with Intel MPI. Is there a more standard approach to returning the user to their own code or does it vary by programming model and implementor? And specifically with Intel MPI would there be a good breakpoint to set in this scenario? Thanks much, Alex -- Alex Zahdeh | PE Debugger Development | Cray Inc. [email protected] | Office: 651-967-9628 | Cell: 651-300-2005