NWChem 6.8.1 with MPI support on Ubuntu 18.04. Help?


Just Got Here
I'm attempting to get NWChem to work on a few new Ubuntu 18.04 workstations with MPI support. Installing from .deb packages worked fine, but MPI doesn't work properly.

I've tried compiling it myself, but I can't seem to get it to work properly. I followed the basic instructions from the documentation under "NWChem 6.6 on Ubuntu 14.04" (http://nwchemgit.github.io/index.php/Compiling_NWChem#NWChem_6.6_on_Ubuntu_14.04_.28Trusty_T...), but something appears to be missing. I can't get any runs to complete successfully after compiling.

Can anyone help me to either:

1: Get the .deb installed version of NWChem 6.8.1 to work with MPI on Ubuntu 18.04?

2: Or, compile NWChem properly on Ubuntu 18.04?

Thanks in advance!

Forum Vet
Could you try to install the .deb packages from

https://github.com/nwchemgit/nwchem/releases/download/6.8.1-release/nwchem-data_6.8.1+133+...
https://github.com/nwchemgit/nwchem/releases/download/6.8.1-release/nwchem_6.8.1+133+gitge...

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!

Forum Vet
This behavior might be due to the threaded BLAS/LAPACK that are spawning multiple threads to maximize CPU usage.
To prevent this, please add the following env. variables settings to your environment

export OMP_NUM_THREADS=1
export OPENBLAS_NUM_THREADS=1
export GOTO_NUM_THREADS=1


Forum >> NWChem's corner >> Compiling NWChem