How to split cufftPlan and cufftExec

It seems that a pair of cufftPlan and cufftExec for calculating the cufft, should be exists together.
I have a big loop with calculating the cufft.
So, I want to split cufftPlan and cufftExec for performance optimization.
I can split them? thus, i wanna put the cufftPlan in initialization part, so it’s called once in initialization.
But I have to process cufft in batch mode, and batch count differs time to time.
At cufftPlan1d(&plan, nX, CUFFT_C2C, nBatch), nBatch is a variable.
What i want is impossible?
Please help me.

I think it is not possible because at plan creation the memory for intermediate stages is allocated according to http://docs.nvidia.com/cuda/cufft/#cufft-setup. There, it is mentioned that the size scales with nBatch. A solution would be to plan for all possible batch sizes in advance (if all the plans fit in memory).

ok, thanks hadschi118.