On Fusiong APU, is it only windows platform supporting the shared memory between multiple devices, like GPU and CPU?
What exactly do you mean by "share memory"? The hardware itself dictates that the GPU's global memory uses the same physical memory DIMMs as the CPU, so yes, in that sense they "share" memory.
If you're talking about zero copy functionality in OpenCL, Linux currently does not support any zero copy memory objects.
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