I have no idea what you mean by "cell sizes per core". Certainly not any terminology within OMPI...


On Dec 15, 2010, at 3:47 PM, Vaz, Guilherme wrote:


Dear all,

I have a problem with openmpi1.3, ifort+mkl v11.1 in Ubuntu10.04 systems (32 or 64bit). My code worked in Ubuntu8.04 and works in RedHat based systems, with slightly different version changes on mkl and ifort. There were no changes in the source code.
The problem is that the application works for small cell sizes per core, but not for large cell sizes per core. And it always works for 1 core. 
Example: a grid with 1.2Million cells does not work with mpiexec -n 4 <my_app> but it works with mpiexec -n 32 <my_app>. It seems that there is a maximum of cell/core. And it works with <my_app>.

Is this a stack size (or any memory problem)? Should I set the ulimit -s unlimited not only on my bashrc but also in the ssh environment (and how)? Or is something else?
Any clues/tips?

Thanks for any help.

Gui




<imagec393d1.JPG><image4c4685.JPG>

dr. ir. Guilherme Vaz

CFD Researcher

Research & Development

 

MARIN

 

2, Haagsteeg
E G.Vaz@marin.nlP.O. Box 28T +31 317 49 39 11
6700 AA WageningenF +31 317 49 32 45
T  +31 317 49 33 25The NetherlandsI  www.marin.nl


_______________________________________________
users mailing list
users@open-mpi.org
http://www.open-mpi.org/mailman/listinfo.cgi/users