mpi and if processIsMaster()

[esp]

i am running a simple test script using mpi, where the script says:

Code

if processIsMaster():
  print "master"
else:
  print "slave"

I set it up for 4 nodes of 8 processors each, and after running it printed master 32 times .. what does it mean? I ran as below:

Code

module load intel
module load pmpi/intel
mpirun -np 32 $ATK_BIN_DIR/atkpython $SRC_DIR/$SCRIPT1   ..otherstuff..

[esp]

sorry this is more appropriat for the installation section, it will not let me delete it

[Nordland]

It means that it is not running in parallel.

[esp]

and this?

MPI Application rank 3 exited before MPI_Init() with status 0

[Anders Blom]

The first issue, about several "master" statements, means that you are most likely not using MPICH2, but rather some other MPI library like OpenMPI. ATK only works with MPICH2 and compatible libs, like Intel MPI or MVAPICH2.

Until that is fixed, the second error is perhaps not relevant.

[esp]

ok thank you

i did check with the admin people who run the machines, they said:

"Things have changed. One major one is the OS, from SLES to CetOS.
Please recompile your code inc needed libraries and run the job."

I have never heard of these OS, my understanding was that the machines were linux ... i will see what i can find out, or if i can install mpich myself .. they have the following MPI implementations already installed:


Compiler  Platform MPI  OpenMPI   Intel MPI
Intel    intel pmpi/intel    intel ompi/intel    intel impi/intel
GNU    gcc pmpi/gnu    gcc ompi/gnu    gcc impi/gnu

i will look into it thank you

[esp]

yes although i did use their implementations before without issue, now i have issues, and i installed mpich2 myself, and it seems to be working, thank you

[esp]

the admins are telling me for mpi needs i need to use openmpi .. i try but it is not running in parallel .. am i correct ATK will not work with openmpi?

[Anders Blom]

That is correct, ATK only works with MPICH2 and its "derivatives", like Intel MPI and MVAPICH2 (those are the ones we have tested with, but there are other ones too).