Setting parallel processing environment variables

The XLSMPOPTS environment variable sets options for program run time using loop parallelization. Suboptions for the XLSMPOPTS environment variables are discussed in detail in Suboptions of the XLSMPOPTS environment variable for parallel processing.

If you are using OpenMP constucts for parallelization, you can also specify runtime options using OMP environment variables, as discussed in OpenMP environment variables for parallel processing.

When runtime options specified by OMP- and XLSMPOPTS environment variables conflict, OMP options will prevail.

You must use thread-safe compiler mode invocations when compiling parallelized program code.