Best practice for multiple validation datasets

[ginfantem]

Hello everyone, I have multiple validation datasets that I pass to the trainer as an OrderedDict. At each validation epoch I might want to process one of them exclusively, in an interleaving fashion. However, even I can conditionally process each dataset via the dataloader_idx argument, validation_step is run also for all the batches for the rest of dataloaders (even though inside validation_step the flow discards them due to the if statement). Is there a best practice around this, so this does not slow down the training process?