Explanation of OpenMP and MPI

Question

A few minutes ago I stumbled upon some text that reminded me of something that had been reflecting on my mind for some time, but I had nowhere to ask.

So, in the hope, this could be a place where people have experience of both, I was wondering, can anyone explain the difference between OpenMP and MPI?

I read the entire Wikipedia article, figured it out in segments, but I'm still thinking; for a Fortran programmer who wants one day to enter the world of parallelism (just learning the basics of OpenMP now), the more reliable way to go?

I would be grateful for all your comments.

Answer 1

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Answer 2

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Answer 3

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We have OpenMP and MPI versions of our software (Fortran), and customers use them depending on their needs.

Given current trends in multi-core architecture, OpenMP-MPI Hybrid is another viable approach.