Sections

The OpenMP sections directive provides a means by which different threads can run different parts of the program in parallel. Copy the code from the appropriate link below to create the executable omp_sections.

Try running the executable omp_sections using different values of OMP_NUM_THREADS.

In this example, there are three functions, times_table, countdown and long_loop. These three functions are called from within an OpenMP sections directive, where each function is placed into a separate OpenMP section. This tells the compiler that these three functions can be called in parallel, and a thread from the team can be assigned to each section. Note that if there are more sections than threads, then each section is queued until a thread is available to run it, while if there are more threads than sections, then the extra threads will have nothing to do. Note that there is no guarantee as to the order in which sections are executed.


Compare with MPI


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