NWChem 6.8.1 with MPI support on Ubuntu 18.04. Help?


Click here for full thread
Just Got Here


@Edoapra Thank you for your help here, and sorry about the email regarding the Google Group, I forgot I had already posted here.

Long story short, I installed the .deb packages for NWChem and it seemed to work fine, but the professor reported a problem with MPI compatibility. He's running a computational server with 72 usable CPU cores, so he needs to be able to tell NWChem how many cores to use so he can run other processes on the server simultaneously.

As of now, if he runs
mpirun -n 20 nwchem in
, for example, it doesn't run just 20 processes and use 20 cores. It runs far more processes and maxes out all 72 CPU cores at 100%. This same behavior happens when we try either the .deb version or ones I've compiled manually.

Any thoughts or ideas on how to proceed, or what the problem might be? Thanks in advance!