[mpich-discuss] processor print out

[Dave Goodell]

On May 20, 2011, at 9:34 AM CDT, Ryan Campbell Crocker wrote:

> I am using a code developed by someone else and it seems like the I/O (print,write) is turned off or blocked for all but the root processor.  What MPI call would be responsible for this.  I'm sure this is a simple fix.

What version of MPICH2 are you using?  Which process manager?  Is this on a cluster where you have direct access via "mpiexec" or is there a batch scheduling system?

This isn't behavior that is controlled (or even specified) by the MPI standard or any MPI routines.  It's entirely implementation-dependent behavior that is typically influenced most heavily by the process manager.  AFAIK all stock MPICH2 process managers (even the deprecated ones) should support this correctly when used normally, but batch scheduling systems like PBS or SLURM might interfere.

-Dave