Setting the Number of Threads Using an OpenMP* Environment Variable

You can set the number of threads using the environment variable OMP_NUM_THREADS. To change the number of OpenMP threads, in the command shell in which the program is going to run, enter:

set OMP_NUM_THREADS=<number of threads to use>.

Some shells require the variable and its value to be exported:

export OMP_NUM_THREADS=<number of threads to use>.

You can alternatively assign value to the environment variable using Microsoft Windows*OS Control Panel.

See Also