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chitharenjan May 1, 2011 04:20

Run openFoam in Multithreads

I am running OpenFoam in my PC. , which have following specifications

Operating System: Ubuntu 10.10 32 bit
Processor: i5, 2 cores and 4 threads

But whenever I am monitoring the openFoam processing, it shows it is only using single thread. I heard that there is a way to run openFoam simultaneously in all my cores. Please help me...

Thank you in advance.

santos May 1, 2011 06:57


Make sure you run your solver with:

mpirun -np 4 <solvername> -parallel


chitharenjan May 1, 2011 15:30

Sequence of Parallel Implimenation
Thank you very much,

That worked perfectly.But I have some more doubts..

1, What is the sequence for running a parallel implementation. I mean for blockMesh and decomposePar, which one I should run first ?

2, I have used a stop watch to compare the speed gain in parallel processing from the normal processing. My processors were running at full load in parallel processing, but the speed gain was negligible. Why is it happening ? Do you have any suggestions in it ?

Waiting for your reply.

JunaidAhmad May 2, 2011 04:05

Can this Command works as it is on GPU base computers

Regards Junaid

akidess May 2, 2011 04:07

1. First mesh, then decompose.
2. There are lots of threads on the forum and the Internet in general on this topic, go have a look. In short, parallelization is no guarantee for speedup. Your problem has to be suitable for your parallel environment.

chitharenjan May 2, 2011 11:07


Comments were helpful.


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