it takes too long time that nppiMalloc_8u_xx function called first time is completed.

Accelerated Computing GPU-Accelerated Libraries
1

Hi

I call nppiMalloc_8u_xx function to resize image and for color space conversion.
it takes too long time that only nppiMalloc_8u_xx function called first time in codes is completed.
it is about 640ms.

Nothing is wrong with it?

Nvida Graphic Adapter : Quadro M2000(m206)

////////////////////
int nSrcStep = 0;
Npp8u * rgbSrcDev;
rgbSrcDev = nppiMalloc_8u_C3(1280,720,&nSrcStep); ← first time called nppiMalloc_8u_xx function

2

CUDA itself and most of the libraries that ship with CUDA have internal state (also referred to as a “context”), so the first API call tends to trigger initialization of the entire software stack. That first API call is often a memory allocation call, for obvious reasons. 640ms sounds a bit long, maybe this is a fairly slow computer?

With the correct timing methodology, this one-time startup overhead for context initialization should not matter. If this is a problem, you can trigger initialization of the CUDA context with a call to cudaFree(0) in a more opportune place; note that this doesn’t initialize NPP though, so there may still be residual startup overhead for that.

3

Also, if you’re not using CUDA 8, switch to CUDA 8. Some modifications were made to npp library structure in CUDA 8 to improve first-time initiialization overhead.