Type = Integer(+)

This is an advanced MPI parameter. MPICORES may be specified to invoke the mpiexec command by defining the number of processes to launch according to the -np command line argument. This value should not exceed the number of user classes, and will be set to the maximum number of user classes if it does. MPICORES x NCORES is the total number of cores that can be used by the program. Note that MPICORES is at a higher level than NCORES, each MPI core will use NCORES for a single user class. E.g. if a computer has 12 cores and MPICORES=5, then the most NCORES can be is 2 (will be reduced by the CPU regardless of input value) and each MPI core will utilize 2 total cores. In this case, the program will only use 10 cores of the 12 available to the computer. If on the other hand MPICORES were set to 4, then NCORES could be as high as 3, and all 12 cores would be utilized. This is important to keep in mind when choosing how to assign the total number of CPU cores on a computer for a given problem. This topic is discussed more in the best practices section of this guide. This parameter cannot be used with the MPIHOSTS parameter, but if using the MPIHOST or MPIMACHF parameters it must be specified or only a single process will be started by mpiexec.