Prerequisites - cmyoo/cosmos GitHub Wiki

Prerequisites for COSMOS

• COSMOS is assumed to run in a linux-like environment including the Windows Subsystem for Linux (WSL). COSMOS requires the following software for compiling and running.

  • GNU Make (make): This may be installed in most unix-like systems.

  • B shell (bash): Any shell can run the code, but it differs how to set an environment variable like OMP_NUM_THREADS. In our document, bash is assumed to set such environment variables.

  • C++ compiler (g++): COSMOS is well-tested with the GCC, but Intel Compiler or PGI Compiler may also be used.

  • OpenMP (Optional): It saves the simulation time when your PC has more CPU cores.

• About C++ compiler with an OpenMP package

  • Depending on the environment, one may have to edit the makefile appropriately.

  • For a Linux PC, the default makefile can be used with g++ compiler.

  • For a Mac PC, one may have to install an OpenMP package in addition to a C++ compiler when the OpenMP is used for parallelization. The std compiler option would have to be altered to an appropriate one (e.g. -std=c++14).

• NOTE: When performing test calculations on a low-spec PC, such as a laptop PC, the calculation speed (especially for the apparent horizon finder) may drop significantly unless the number of threads for OpenMP is kept small. For such test calculations, a user may have to limit the number of cores to one or at most a few with export OMP_NUM_THREADS=x (x: number of threads).