Metrics not on same device as Trainer/model

[mandeep-starling]

When running on a CUDA device, the following code:

from pytorch_widedeep import Trainer
from torchmetrics.classification import BinaryAUROC, BinaryPrecision, BinaryRecall

trainer = Trainer(model, objective="binary", metrics=[BinaryAUROC(), BinaryPrecision(), BinaryRecall()])

Returns error:

RuntimeError: Expected all tensors to be on the same device, but found at least two devices, cuda:0 and cpu!
...
  File "/opt/conda/lib/python3.10/site-packages/pytorch_widedeep/utils/general_utils.py", line 12, in wrapper
    return func(*args, **kwargs)
  File "/opt/conda/lib/python3.10/site-packages/pytorch_widedeep/training/trainer.py", line 524, in fit
    train_score, train_loss = self._train_step(
  File "/opt/conda/lib/python3.10/site-packages/pytorch_widedeep/training/trainer.py", line 1000, in _train_step
    score = self._get_score(y_pred, y)
  File "/opt/conda/lib/python3.10/site-packages/pytorch_widedeep/training/trainer.py", line 1049, in _get_score
    score = self.metric(torch.sigmoid(y_pred), y)
  File "/opt/conda/lib/python3.10/site-packages/pytorch_widedeep/metrics.py", line 40, in __call__
    metric.update(y_pred, y_true.int())  # type: ignore[attr-defined]
  File "/opt/conda/lib/python3.10/site-packages/torchmetrics/metric.py", line 486, in wrapped_func
    raise RuntimeError(
RuntimeError: Encountered different devices in metric calculation (see stacktrace for details). This could be due to the metric class not being on the same device as input. Instead of `metric=BinaryPrecision(...)` try to do `metric=BinaryPrecision(...).to(device)` where device corresponds to the device of the input.

I could manually try to do this on my end, by getting the device from here and setting it. But I wonder if this should work out of the box?

I read some discussion in pytorch-lightning here and here where it seems there is a way for metrics to be automatically moved to the same device as the model?

[jrzaurin]

@5uperpalo I am traveling. If you have a sec maybe you could have a look?

Otherwise ill have a look in the next coming days

[jrzaurin]

Hey @mandeep-starling

there are a number of ways we could tackle this.

One is, as you suggest, getting the device from the Trainer and pass it to the metrics like

trainer = Trainer(model, objective="binary", metrics=[BinaryAUROC().to(device), ...]

I can also set it up internally, but that involves some complications depending whether a user decides to use the nn.Module
lightning metrics or their functional version.

I will think about it. I might branch out and you could try see what you prefer.