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mpirun with two .ini-files?

Posted: July 08 2015
by Katharina Borm
Hi,
is there a nice way to run cosmomc with two different .ini-files at the same time?
Usually, I run something like

mpirun -np 4 ./cosmomc params.ini

to obtain four chains, each on a different core. If I launch a second process after this, for example

mpirun -np 4 ./cosmomc params2.ini

I get another four chains for the second process, but they are sharing the cores of the first process. So, I get eight chains, running on only four cores.
I found another option as

mpirun -np 4 ./cosmomc params.ini : -np 4 ./cosmomc params2.ini

In this case, I get eight cores in total each with one chain, but the chains are "only" for the first process with params.ini. So, I have too many chains for params.ini and none for params2.ini.

Does anyone know how to solve this problem?
Thanks in advance for any idea!

cheers, Katharina

Re: mpirun with two .ini-files?

Posted: July 08 2015
by Antony Lewis
Katharina Borm wrote:Hi,
is there a nice way to run cosmomc with two different .ini-files at the same time?
Usually, I run something like

mpirun -np 4 ./cosmomc params.ini

to obtain four chains, each on a different core. If I launch a second process after this, for example

mpirun -np 4 ./cosmomc params2.ini
Normally this would work fine. If it does not, and you are submitting via a queue, check the submission script; also things like "omplace" and "dplace" options depending on your machine, and various I_MPI_PIN variables etc options you can see in the sample job_script submission script provided.