In an application cannot ippAlgHintFast and ippAlgHintAccurate be used?

[maverick6664]

I am modifying SETI@home, which uses fft in some portion. To make it faster, I replaced original fft's (actually cdft functions) with IPPs. I seem to need to use ippsFFT* functions with ippAlgHintFast hint and ippAlgHintAccurate. At first ippAlgHintAccurate is used only a few times, then ippAlgHintFast many times.

Then I found it's evidently much slower than the one with ippAlgHintFast in all fft functions. And at the same time the application version with ippAlgHintFast in all ippsFFT* functions is as fast as the one with original dft functions and ippsFFT* with ippAlgHintFast (ie, much faster).

So I suspect this hint values (ippAlgHintFast/Accurate) shouldn't be mixed in an application....am I correct?

Thanks in advance!

[Vladimir_Dudnik]

Hi,

we need more information to provide correct answer. So, could you please specify which version of IPP did you use, on which platform and which IPP functions did you call and what were parameters?

Regards,

Vladimir