So I run the test on a compute node with four device [0, 1, 2, 3], where device 1 and device 2 are accessible to me (by using nvidia-smi). When I run CUDA_VISIBLE_DEVICE=1 python3.6 train.py, the device printed out for position, mask and input are still
position: cuda:0
mask    : cuda:0
input   : cuda:0