If the application "ensures" that there are no messages in-flight, then I agree with you. I was thinking of applications that use asyncronous MPI communication in a multi-threaded env, potentially leading to unmatched messages.....
 
Right, so what would you like MPI to do in that case? Are you focused on the global checkpointing case or the case where each process may checkpoint independently?

Greg Bronevetsky
Post-Doctoral Researcher
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Lawrence Livermore National Lab
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