I would like to see if there are any updates re this thread back from 2010:
I've got 3 boxes at home, a laptop and 2 other quadcore nodes . When the
CPU is at 100% for a long time, the fans make quite some noise:-)
The laptop runs the UI, and the 2 other boxes are the compute nodes.
The user triggers compute tasks at random times... In between those times
when no parallelized compute is done, the user does analysis, looks at data
and so on.
This does not involve any MPI compute.
At that point, the nodes are blocked in a mpi_broadcast with each of the 4
processes on each of the nodes polling at 100%, triggering the cpu fan:-)
homogeneous openmpi 1.10.3 linux 4.7.5
Nowadays, are there any more options than the yield_when_idle mentioned in
that initial thread?
The model I have used for so far is really a master/slave model where the
master sends the jobs (which take substantially longer than the MPI
communication itself), so in this model I would want the mpi nodes to be
really idle and i can sacrifice the latency while there's nothing to do.
if there are no other options, is it possible to somehow start all the
processes outside of the mpi world, then only start the mpi framework once
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