MPI builds

[njzjz]

Comment:

It seems to me that MPI is not enabled in this recipe. I'd like to know if there is any specific reason for it, or if I can contribute to enable MPI.

[mattwthompson]

I don't think there's a reason for it, except that it hasn't been important to our knowledge. Production runs are generally not going to be using these builds, which value portability and reliability over performance.

I think a PR adding separate MPI builds would be welcome, but I'd like to ensure programs running in serial aren't affected. I'm not actually sure the best way to do this; in the GROMACS feedstock we just build several variants and muck with the build number, which is not what the build number is meant to do, but it works: https://github.com/conda-forge/gromacs-feedstock/tree/main/recipe

[jaimergp]

Yea, just lack of volunteer time to implement it and maintain it. Same with CUDA stuff. Ambertools takes a while to build so each attempt is very time consuming if things stop working due to a change somewhere.