Usage of the Linux Clusters at DESY Zeuthen
There are no dedicated parallel clusters available at the moment, but you can run parallel MPI jobs in the SGE farm. The documentation in Batch_System_Usage applies there.
Building Applications
Since SL5, all batch worker nodes have the openmpi implementation of the MPI standard installed.
There are MPI versions for the GCC, Intel and PGI compilers installed:
/opt/openmpi/gcc/bin/mpicc
/opt/openmpi/intel/bin/mpicc
/opt/openmpi/pgi/bin/mpicc
Compilers for C++ and Fortran are available as well.
Building applications
MPI Applications can be compiled on any 64 bit SL5 machine, e.g. sl5-64.ifh.de.
Batch System Access
A job script designated for a parallel job needs to specify the parallel environment and the number of required CPUs. The parameter looks like this:
#$ -pe multicore-mpi 4
Be sure to call the right mpirun version for your compiler. If you application was compiled with GCC, use
/opt/openmpi/gcc/bin/mpirun -np $NSLOTS yourapp
AFS Access
The application binary must be available to all nodes, that's why it should be placed in an AFS directory.
BLAS library
Both ATLAS ans GotoBLAS are available.
- ATLAS is in /opt/products/atlas
- libgoto is in /usr/lib or /usr/lib64 respectively.
Further documentation
HPC-Clusters at DESY Zeuthen , 11/22/06, technical seminar