fix #4209

DeepSpeed ZeRO3 has inflight param error when calling model.eval()


Former-commit-id: 4be013f18ea6a35b5a11db98db5f0670ffb41619

src/llamafactory/train/ppo/trainer.py

@@ -1,6 +1,7 @@
 import math
 import os
 import sys
+import warnings
 from types import MethodType
 from typing import TYPE_CHECKING, Any, Dict, List, Optional, Tuple
 
@@ -136,6 +137,7 @@ class CustomPPOTrainer(PPOTrainer, Trainer):
 
         device_type = unwrapped_model.pretrained_model.device.type
         self.amp_context = torch.autocast(device_type, dtype=model_args.compute_dtype)
+        warnings.simplefilter("ignore")  # remove gc warnings on ref model
 
         if finetuning_args.reward_model_type == "full":
             if self.is_deepspeed_enabled: