topologyQuery cudaDeviceGetP2PAttribute cudaGetDeviceAttribute cudaGetDeviceCount whole ./ ../ ../../Common Performance Strategies Multi-GPU peer to peer CUDA Performance multi-GPU support true topologyQuery.cu 1:CUDA Basic Topics 1:Performance Strategies sm35 sm37 sm50 sm52 sm60 sm61 sm70 sm72 sm75 sm80 sm86 x86_64 linux windows7 x86_64 macosx ppc64le linux all exe