[mpich-discuss] MPI_File_open() fails on local + NFS file system

[Audet, Martin]

Hi MPICH_Developers,

We are unable to use MPI_File_open() on a cluster where the first node (master node) mount a local file system and export it via NFS to a few cluster nodes so that /home on both the master node and the compute node refers to the same directory.

When a job composed on one (or more) process on the master node and one (or more) process on a client node is started, MPI_File_open() to create a new file either make the program to abort (if the process of rank 0 is on the master node using the local file system) or to freeze (if the process of rank 0 is on a compute node acessing the file via NFS).

When the program freeze, an inspection with gdb shows that the process of rank 0 is stuck into a MPI_Bcast() called by MPI_File_open().

Note that this happens with many mpich2 versions from 1.0.7 to 1.4rc2.

So we would like to know if the configuration we use is local or not.

Thanks,

Martin Audet