running multiple partitions on a single processor

Hi all,

In the documentation for neb it states: “Note that if you have MPI installed, you can run a multi-replica simulation with more replicas (partitions) than you have physical processors, e.g you can run a 10-replica simulation on just one or two processors.”

However, I cannot find an example in the doc or on the list on how to run multiple partitions on a single processor. Can someone please give me the appropriate mpirun command with the correct -partition option in order to accomplish this?

Thanks for your time,


Suppose your computer has only 1 physical processor. If you have an MPI installation, you can still do:

mpirun -np 4 lmp_linux -partition 4x1 -in in.neb.hop1

It’s just that now all four MPI processes will be sharing the one processor. At best, it will run 4 times as slow as running on four cores with good memory bandwidth. But you will still get the same answer at the end.



Thanks for your reply, that was easy enough.