mpirun - not enough slots available

mpi openmpi hpc
kilojoules picture kilojoules · Feb 29, 2016 · Viewed 30.9k times · Source

Usually when I use mpirun, I can "overload" it, using more processors than there acctually are on my computer. For example, on my four-core mac, I can run mpirun -np 29 python -c "print 'hey'" no problem. I'm on another machine now, which is throwing the following error:

$ mpirun -np 25 python -c "print 'hey'"
--------------------------------------------------------------------------
There are not enough slots available in the system to satisfy the 25 slots 
that were requested by the application:
  python

Either request fewer slots for your application, or make more slots available
for use.
--------------------------------------------------------------------------

Why isn't "overclocking" mpirun working here? Is there a way I can overcome this error message and successfully run with more processors than are available?

Answer

dwaylooper picture dwaylooper · Oct 14, 2016

Apparently oversubscribing can be attained using the "--oversubscribe" option with mpirun - did the trick for me with running torque/maui

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