The acc in multi gpus is lower than one gpus

Hi, my code is in

I run the will get acc 0.94. But the acc will not higher than 85% with even I set the gpu=0.
Is there any error in my code?

My environment is Pytorch 1.6 and dgl-cu10.2 0.52. You can get the test data example in

Hey @sangyx, when using DDP, you might need to tune the batch size and learning rate a bit. See the discussion below: