Consider the case when you
- Create a FFTW3 plan and use the plan for sequential DFT computation on each thread in your parallel region
- Use Intel Math Kernal Library (Intel MKL) FFTW3 wrappers
- Want the best performance
Intel MKL FFTW3 wrappers are thread safe by default. However, you should set one additional Intel MKL variable to get the best performance with Intel MKL. Set the number_of_users_threads variable as described below.