openmc_install_scripts

This is a set of scripts that are intended to help with installation of OpenMC with its DAGMC-backend and its dependencies.

NOTE: the embree backend is developed by Intel and is known to ''cause issues on AMD processors'' and older Intel processors. For more details, see the EMBREE section.

To install to some given location do:

 ./install-all.sh --prefix=<path>

It is assumed that the installing user has permission to write files at the installing location. The most stable way of handling installation at present is to install to a python venv. Like so:

 python -m venv <path>
 source <path>/bin/activate
 ./install-all.sh --prefix=<path>

This will put all the required libraries etc in that location and ensure the python modules are present.

A variant of this procedure which install to e.g. a system location is the following (assuming that the installing username is and has sudo-permissions)

 sudo mkdir <path>
 sudo chown <user> <path>
 python -m venv <path>
 source <path>/bin/activate
 ./install-all.sh --prefix=$VIRTUAL_ENV

The last step uses an environment variable set by the python virtual environment.

Specifics with Embree

Carefully read the instructions on the embree git for the latest updates: https://github.com/embree/embree

The embree cmake configuration uses ISA-specific hardware acceleration. by default, the EMBREE_MAX_ISA cmake flag is set to AVX2, which is a relatively new addition to the x86_64 instruction set. The following cmake flags may be used to alter your configuration as desired (copied from the embree readme):

• EMBREE_MAX_ISA: Select highest supported ISA (SSE2, SSE4.2, AVX, AVX2, AVX512, or NONE). When set to NONE the EMBREE_ISA_* variables can be used to enable ISAs individually. By default, the option is set to AVX2.

• EMBREE_ISA_SSE2: Enables SSE2 when EMBREE_MAX_ISA is set to NONE. By default, this option is turned OFF.

• EMBREE_ISA_SSE42: Enables SSE4.2 when EMBREE_MAX_ISA is set to NONE. By default, this option is turned OFF.

• EMBREE_ISA_AVX: Enables AVX when EMBREE_MAX_ISA is set to NONE. By default, this option is turned OFF.

• EMBREE_ISA_AVX2: Enables AVX2 when EMBREE_MAX_ISA is set to NONE. By default, this option is turned OFF.

• EMBREE_ISA_AVX512: Enables AVX-512 for Skylake when EMBREE_MAX_ISA is set to NONE. By default, this option is turned OFF.