fft_openmp, a C code which demonstrates the computation of a Fast Fourier Transform in parallel, using OpenMP.
On an Apple PowerPC G5 with two processors, the following results were observed:
Threads | N | Time | MegaFLOPS |
---|---|---|---|
1 | 33,554,432 | 32.65 | 128.4 |
2 | 33,554,432 | 19.87 | 211.0 |
4 | 33,554,432 | 19.80 | 211.7 |
In the BASH shell, the program could be run with 2 threads using the commands:
export OMP_NUM_THREADS=2 ./fft_openmp
The computer code and data files described and made available on this web page are distributed under the MIT license
fft_openmp is available in a C version and a C++ version and a FORTRAN90 version.
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