yuzijiano

Hi~ If you just want set argument `MAX_TOKENS` and filter invalid _valid_set_ samples, maybe you can modify trainer.py [Line749](https://github.com/facebookresearch/fairseq/blob/main/fairseq/trainer.py#L749) from : ``` max_positions=utils.resolve_max_positions( self.task.max_positions(), self.model.max_positions(), ), ``` to : ```...