Dear all,
After read the paper of Nicholas.Karonis "MPICH-G2: A Grid-Enabled
Implementation of the Message Passing Interface" and the MPICH-G2's web page, I
want to ask 2 questions in order to understand MPICH-G2 better.
1. As the paper and the web page said, MPICH-G2 used the vendor-supplied MPI
implemention to perform the intra-communications, and the vendor-supplied MPI
implemention means the MPI implemention that already exists on the cluster and
which is not MPICH-based. But what should I do if my cluster has already
installed MPICH? In this case, how does MPICH-G2 perform the
intra-communications? And if I have already configured my cluster with normal
MPICH, should I remove the installation of MPICH and re-install the MPICH-G2 on
the head node?
2.Nick said the mpich-g2 works based on the infrastructure we already have that
controls access to our cluster. I understand it, but I am still a little
confused about how Globus submit mpi jobs to local schedular (such as PBS).
When my cluster is managed by PBS and have normal MPICH installed,I submit mpi
jobs to PBS using something like "mpriun -machinefile $PBS_NODEFILE -np 10
app". Now I remove the normal MPICH and install MPICH-G2, then the machinefile
used by MPICH-G2 is no longer the nodes of my cluster, but the address of
compute resources in the grid. In this case, how does the PBS jobmanager sumit
mpi jobs to PBS ?
Any help will be appraciated!
Thanks,
Tracy
