Turns out that the way the SLURM plm works
is not compatible with the way MPI processes
on Cray XC obtain RDMA credentials to use
the high speed network. Unlike with ALPS,
the mpirun process is on the first compute
node in the job. With the current PLM launch
system, mpirun (HNP daemon) launches the MPI
ranks on that node rather than relying on
srun.
This will probably require a significant amount
of effort to rework to support Native SLURM
on Cray XC's. As a short term alternative,
have the alps plm (which gets selected by default
again on Cray systems regardless of the launch system)
check whether or not srun or alps is being used on the
system. If alps is not being used, print a helpful
message for the user and abort the job launch.
Signed-off-by: Howard Pritchard <howardp@lanl.gov>