Multiple GPUs Encoder Decoder

[adkuln]

If we use >1 gpu there is an error:
return type(out)(map(gather_map, zip(*outputs)))

TypeError: zip argument #1 must support iteration

[adkuln]

@ibeltagy if i install pytorch-lightning-1.0.3, it works. I will try to train model and check correctness of result

[ibeltagy]

I am using my own fork of PL https://github.com/allenai/longformer/blob/encoderdecoder/requirements.txt#L2. PL is full of bugs and I don't know which release to trust.

[SeanNaren]

hey @ibeltagy! we've recently released PyTorch Lightning v1.0 with a bunch of stability fixes, and are releasing minor version releases to handle edge cases fixes/build towards new features. I'll make a PR to propose upgrading to the stable release!