> > It seems that the calls to collective communication are not > > returning for some MPI processes, when the number of processes is > > greater or equal to 5. It's reproduceable, on two different > > architectures, with two different versions of OpenMPI (1.3.2 and > > 1.3.3). It was working correctly with OpenMPI version 1.2.7. > > Does it work if you turn off the shared memory transport layer; that is, > > mpirun -n 6 -mca btl ^sm ./testmpi
Yes it does, on both my configurations (AMD and Intel processor). So it seems that the shared memory synchronization process is broken. Could be a system bug, I don't know what library OpenMPI uses (is it IPC ?). Both my systems are Linux 2.6.31, the AMD is Ubuntu, and the Intel is an ARCH-linux. --Vincent
