On 04/09/2013 09:50 AM US Central Time, Matthieu Dorier wrote:

Is there any option in Mpich to make sure a line sent to stdout from one rank is not broken by a line sent by another rank when mpirun merges the output of all ranks?

Not when everything is dumped to the same output from mpiexec (e.g., stdout), since that'll require an arbitrary amount of buffering at mpiexec to do that. You could redirect the output to separate per-rank files. mpiexec -help should give you information on that. -- Pavan -- Pavan Balaji http://www.mcs.anl.gov/~balaji