Hi Pavan, To rephrase, I am interested in understanding when would MPI_Wait() block indefinitely, waiting for other process to make progress. I believe that your response answers my question. Thanks again. --Jiri On Wed, Jun 26, 2013 at 4:48 PM, Pavan Balaji <[email protected]> wrote:

Hi Jiri,

On 06/26/2013 03:08 PM, Jiri Simsa wrote:

...

Thank you for your quick answer. I am trying to understand the blocking behavior of MPI_Wait in the case of non-blocking collectives. Is it safe to assume that, for a non-blocking collective, MPI_Wait is guaranteed to return once all other processes call the corresponding completion operation (e.g. MPI_Wait or MPI_Test)?

I'm not sure I understand your question. Are you asking if MPI_WAIT in a process is guaranteed to return after some finite amount of time after every other process has called MPI_WAIT? Then, yes.

-- Pavan Balaji http://www.mcs.anl.gov/~balaji