Pytorch如何使用多块GPU同时训练

记录一下：
If you want to use all the available GPUs:

device= torch.device("cuda"if torch.cuda.is_available()else"cpu")

model= CreateModel()

model= nn.DataParallel(model)
model.to(device)

If you want to use specific GPUs: (For example, using 2 out of 4 GPUs)

device= torch.device("cuda:1,3"if torch.cuda.is_available()else"cpu")## specify the GPU id's, GPU id's start from 0.

model= CreateModel()

model= nn.DataParallel(model,device_ids=[1,3])
model.to(device)