Changes to environment modules, Monday 4/30 at noon - Completed

UPDATE April 30th, 2018:

1. We are now allowing only one compiler loaded at a time.
   
   With this change, we have removed the compiler tag in the module versions, in particular for MPI distributions and some libraries such as FFTW or NetCDF. In the past, we would denote e.g. MPICH built with GCC as mpich/3.2.g. Now we have mpich/3.2, the compiler being handled by the modules hierarchy.
2. We added the MPI hierarchy to some HDF5 and Boost modules that use MPI.
   
   Now we have new modules phdf5 and pboost along with the serial hdf5 and boost. Since all HDF5 and Boost builds that include MPI also contain the serial components, the serial part has been kept in the old modules and should not require user end adjustments.
   
   If you started receiving errors about missing modules, please check your environment (~/.custom.[sh,csh]) and batch job scripts for occurences of the explicit MPI and other libraries (such as boost and fftw) versioning (g=GNU, i=Intel, p=PGI), and for need to use phdf5 or pboost instead of hdf5 and boost.

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On Monday, 4/30, at noon we will be updating the environmental modules application, Lmod, along with some changes to the modules hierarchies.

In particular, we are going to restrict having only one compiler loaded at a time - a change from the past where there was no such restriction. We are doing this to avoid problems we have seen when two compilers do not coexist well together. This also moves us to be more in line with practices at other HPC resources.

With this change, we are removing the compiler tag in the module versions, in particular for MPI distributions and some libraries such as FFTW or NetCDF. In the past, we would denote e.g. MPICH built with GCC as mpich/3.2.g. Now we will be having mpich/3.2, the compiler being handled by the modules hierarchy.

Therefore, we ask users to please check their environment (~/.custom.[sh,csh]) and batch job scripts for occurences of the explicit MPI and other libraries (such as boost and fftw) versioning (g=GNU, i=Intel, p=PGI) and adjust accordingly.

The second change is that we added the MPI hierarchy to some HDF5 and Boost modules that use MPI, naming the modules phdf5 and pboost, as compared to the serial hdf5 and boost. Since all HDF5 and Boost builds that include MPI also contain the serial components, the serial part has been kept in the old modules and should not require user end adjustments.

Note that these changes will affect queued up jobs as the job script is processed at the job submission time, but not running jobs where the modules have been already loaded. Therefore we recommend that those users who do have the compiler specific module files in their job scripts either delete their jobs before Monday noon, or let them crash (due to non-existing module file and subsequent missing mpirun or other executable/library) and resubmit new ones after the Monday noon switch.

If you have any questions or concerns with this change please let us know at helpdesk@chpc.utah.edu.