P2P mem transfer between multiple CPU processes

After viewing the webinars on GPU-Direct/UVA and Multi-GPU, I am still confused about whether it is possible to perform a P2P mem copy between 2 GPU’s when each GPU context is owned by a different CPU process. I have looked at the SDK example, threadMigration, and I see how it is possible to perform a P2P copy from different threads within a single process, however I am wondering if it is possible to access a GPU’s memory pointer between 2 CPU processes using an IPC shared memory space. Is this possible, or does the UVA structure make this impossible? Thanks for your reply.

It is possible in CUDA 4.1 with the cudaIpc* functions.

Thanks, I’ll take a look.