we have a little cluster with:
- a master (2*4 cores)
- 8 nodes (2*6 cores per node)
- infiniband (DDR connectX)
- we are using the Intel Cluster Toolkit. I_MPI_FABRIC is set to "shm:ofa".
I'm trying to optimize the use of the mpi library with "mpitune". And I have a few questions...
- Does "mpitune" work under a batch system like torque ohne special tricks ? at the moment I have to define a --ppn-range to limit mpitune. If i'm starting a job with "nodes=1:ppn=4" I have to limit mpitune with "--ppn-range 1:4". Is there a better way ?
- If I run "mpitune" on the full cluster, mpitune will generate a lot of files (for example mpiexec_shm-ofa_nn_1_np_2_ppn_2.conf) for each configuration. What should I do with these files ? Can I just copy them under the etc directory of impi and the a "mpiexec -tune" will use the correct file ? For example if I'm running a job with "nodes=2:ppn=4", will mpiexec select the good tuning conf file automaticly ?
Thx a lot!