Setting number_of_user_threads for Intel® Math Kernel Library FFTW3 wrappers

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.

In C:

#include "fftw3.h"

  • Intermediário
  • Biblioteca kernel de matemática Intel®
  • OpenMP*
  • FFT
  • FFTW
  • FFTW3
  • fourier transform
  • MKL FFTW3 wrappers
  • number_of_users_threads
  • Otimização
  • Computação paralela
  • Thread
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  • Desenvolvedores
  • C/C++
  • Compilador C++ Intel®
  • Intel® Cilk™ Plus
  • Depurador JTAG Intel®
  • Primitivas Intel® Integrated Performance
  • Biblioteca kernel de matemática Intel®
  • Intel® System Studio
  • Intel® Inspector
  • Intel® VTune™ Amplifier
  • FFT
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    Intel® Math Kernel Library (Intel® MKL) includes the optimized DFT transform functions on Intel® Xeon Phi™ coprocessors. These functions are carefully vectorized and threaded to take advantage of the hardware features. This article provides some performance tuning tips on running MKL DFT function on Intel Xeon Phi coprocessors.  We will start with some simple example code.

    Building the example code

  • Desenvolvedores
  • Linux*
  • Servidor
  • C/C++
  • Fortran
  • Principiante
  • Intermediário
  • Biblioteca kernel de matemática Intel®
  • MIC
  • Xeon Phi
  • DFT
  • FFT
  • performance
  • offload
  • Extensões Intel® Streaming SIMD
  • Arquitetura Intel® Many Integrated Core
  • Assine o FFT