64-bit kernel for Mac Pro

I am wondering what kind of application I am developing and 64 bit addressing. I would like to use about 12GB 32GB on a Mac Pro.

Here's the thing, the kernel is not 64-bit in Snow Leopard on my Mac Pro (efi 32-bit). I'm wondering though if I can fix this problem then maybe 4GB per app even if the kernel is only 32-bit.

This is mainly about the card data and the set is about 12GB and I want it to be fast ... no page swapping.

thanks for the help

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