[Pw_forum] problems with running Quantum Espresso in parallel

[torstein.fjermestad at unito.it]

Dear all,

I recently installed QE on a virtual cluster configured with 
StarCluster.
QE configures and compiles without errors. However, when I submit a 
parallel calculation on 16 processors, the following is written near the 
start of the output file:

Parallel version (MPI), running on     1 processors

The line is repeated 16 times in the output. To me it seems like I am 
actually running 16 single processor calculations that all write to the 
same output file (stdout in this case).

The way I submit this calculation, is the following:

I write the following submit script (submit.sh):
cp /path/to/executable/pw.x
mpirun -np 16 pw.x -in input.inp

Then I submit the job with the following command:

qsub -cwd -pe orte 16 ./submit.sh

The queuing system of StarCluster is Open Grid Scheduler.

For the line in the submit script, I have also tried several 
alternatives such as:

mpirun pw.x -in input.inp
mpirun pw.x -inp input.inp
mpirun -np 16 pw.x -inp input.inp
mpirun -np 16 pw.x < input.inp

In the archives of this mailing list I have seen some similar problems, 
but in spite of this I was still not able to solve my problem.

I would appreciate very much if someone could give me suggestions on 
how to solve the problem.

Thanks in advance.

Yours sincerely,
Torstein Fjermestad
University of Turin,
Italy