Hi,
It requires to allocate with ‘gpu::CudaMem::ALLOC_ZEROCOPY’ if you want to use memory mapping.
By the way, related information shown with deviceQuery in cuda sample.
./NVIDIA_CUDA-8.0_Samples/1_Utilities/deviceQuery/deviceQuery
Run time limit on kernels: Yes
Integrated GPU sharing Host Memory: Yes
Support host page-locked memory mapping: Yes
Alignment requirement for Surfaces: Yes
Device has ECC support: Disabled
Device supports Unified Addressing (UVA): Yes
Device PCI Domain ID / Bus ID / location ID: 0 / 0 / 0
Compute Mode:
< Default (multiple host threads can use ::cudaSetDevice() with device simultaneously) >
deviceQuery, CUDA Driver = CUDART, CUDA Driver Version = 8.0, CUDA Runtime Version = 8.0, NumDevs = 1, Device0 = NVIDIA Tegra X1
Result = PASS