Hi, We would need more information to determine if this error is caused by an MPICH bug. Could you please post the code which is failing along with some sample input for both failing and non-failing cases? Thanks, Antonio On Wednesday, May 15, 2013 07:19:59 PM Mahesh Doijade wrote: Hi, I am dynamic creating process using MPI_Comm_spawn_multiple(), the code runs for several inputs without any error but for some larger input size it is throwing this error as given below. Fatal error in PMPI_Barrier: A process has failed, error stack: PMPI_Barrier(426).........: MPI_Barrier(comm=0x84000002) failed MPIR_Barrier_impl(333)....: Failure during collective MPIR_Barrier_impl(315)....: MPIR_Barrier_intra(83)....: dequeue_and_set_error(823): Communication error with rank 0 =================================================================================== = BAD TERMINATION OF ONE OF YOUR APPLICATION PROCESSES = EXIT CODE: 1 = CLEANING UP REMAINING PROCESSES = YOU CAN IGNORE THE BELOW CLEANUP MESSAGES =================================================================================== [proxy:1:0@clusterslave3] HYD_pmcd_pmip_control_cmd_cb (./pm/pmiserv/pmip_cb.c:883): assert (!closed) failed [proxy:1:0@clusterslave3] HYDT_dmxu_poll_wait_for_event (./tools/demux/demux_poll.c:77): callback returned error status [proxy:1:0@clusterslave3] main (./pm/pmiserv/pmip.c:210): demux engine error waiting for event [mpiexec@clusterslave3] HYDT_bscu_wait_for_completion (./tools/bootstrap/utils/bscu_wait.c:76): one of the processes terminated badly; aborting [mpiexec@clusterslave3] HYDT_bsci_wait_for_completion (./tools/bootstrap/src/bsci_wait.c:23): launcher returned error waiting for completion [mpiexec@clusterslave3] HYD_pmci_wait_for_completion (./pm/pmiserv/pmiserv_pmci.c:216): launcher returned error waiting for completion [mpiexec@clusterslave3] main (./ui/mpich/mpiexec.c:325): process manager error waiting for completion -- Regards, -- Mahesh Doijade