| [ptp-user] Launcher Needs Place to Specify Arguments to Mpiexec |
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Hi, I
have installed the 2.0 release and it fixes many of the problems I was having. In
addition, it appears to work with MPICH2, which is what we use here, so that is
all good. PTP is coming along. However
using MPICH2 brings me back to the problem I had with OpenMPI, how to specify
which hosts to use (and to specify other arguments to mpiexec in general).
I got around this with OpenMPI by settings the hosts in MPI_HOME/etc/openmpi-default-hostfile
rather than using mpiexec –machinefile. However, I still didn’t
have the finer control that arguments to mpiexec would give. Unfortunately,
this workaround doesn’t work with MPICH2. MPICH2 starts daemons on
the head node and on other nodes in the file specified by mpdboot –f <file>.
It will then use the _head node_
for running programs as well as the ones in <file>, which we don’t
want to happen. It can’t be fixed as with OpenMPI. I could
fix it if I could use mpiexec –machinefile. A
second point is that now that I am running both OpenMPI and MPICH2, it would be
nice to be able to use mpiexec –prefix so the nodes can find the OpenMPI
files rather than the MPICH2 ones, which are the default from .cshrc. (I
can start Eclipse with the PATH set to OpenMPI so ORTE works, but I haven’t
found a way to pass this on to the nodes. Consequently, I have to change
my .cshrc and log in again to use OpenMPI.) In
general, there are many other arguments to mpiexec that should be available. There
should be a box in the launcher Arguments tab for arguments to the program (as
is there now) _and_ also to
mpiexec (which is not there). The
situation is the same as for launching Java programs, where you specify
arguments to the program _and_ to
the VM. It doesn’t seem like this would be hard to implement. Thanks, -Ken |