mpirun with Intel OneAPI running processes n times

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I am new to Intel OneAPI, but I installed the OneAPI package and when I run mpirun -n ...

I receive an output like the following if I set N = 3 (for example):

Iteration #1... Iteration #1... Iteration #1... Iteration #2... Iteration #2... Iteration #2...

Rather than dividing the cores I specify to the program, it rather runs the program N times with 1 core divided to each process. I was wondering how to set this up so that N cores are divided to 1 process.

Other useful information is that I am running a program called Quantum Espresso and I am running this program with a NUMA 2x18 core dual processor with 2 threads for each core. I initially installed Intel OneAPI because I noticed that if I specify 72 cores with mpirun, the computational demand increases 50-60 fold as opposed to running with 1 core and was hoping OneAPI may be able to resolve this.

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TonyM On

So mpirun with -np will say how many instances of a given process to run as you saw.

Have you read this part of their documentation?

https://www.quantum-espresso.org/Doc/user_guide/

I’m not sure how you’ve built it or which functions you are using, but if you have built against their multithreaded libraries with OpenMP then you should get N threads in a process for those library calls.

Otherwise you will be limited to the MPI parallelism in their MPI parallel code.

I’m not sure what you expect when you said you use all 72 code and the computational demand increases? Isn’t that what you want, with the goal that the final result is completed sooner? In either the OpenMP or MPI cause you should see computational resource usage go up.

Good luck!