添加了 torch_driver.load_model 在ddp 时出现显存爆炸的todo事项

fastNLP/core/drivers/torch_driver/torch_driver.py

@@ -190,6 +190,7 @@ class TorchDriver(Driver):
         :param load_state_dict: 保存的内容是否只是权重
         """
         model = self.unwrap_model()
+        # todo torch.load 在加载时会使得卡 0 多出一个（甚至多个）model 的显存；因此在多卡断点重训时可能会出现错误；
         res = torch.load(filepath, map_location='cpu')
         if isinstance(res, dict) and only_state_dict is False:
             logger.rank_zero_warning(f"It seems like that {filepath} only contains state, you may need to use "