fgeorgatos
commented
11 years ago fyi. http://harpon.lkb.upmc.fr/wiki/index.php/Installation_hints_for_various_software#FFTW "Performances of FFTW for 1 thread are slighlty lower than MKL, but better for 2 or more threads, for MKL is bad (no speed-up or some slow-down). " ...
oops; if the above is true it basically means there may be good reasons for following a more mix-n-match approach as regards the glueing of FFT with other libraries (MKL Linear Algebra in mind here).
Although Intel MKL provides FFTW wrappers, they're optional at build time.
When they are missing, the framework will refuse to set
FFT_LIB, which makes sense (see #518).We should define and support an alternative toolchain that uses all the Intel tools, but relies on the FFTW library for FFT support, as opposed to Intel MKL.