diff --git a/examples/merge_lora/llama3_full_sft.yaml b/examples/merge_lora/llama3_full_sft.yaml
index 3d5682a7..4e329fad 100644
--- a/examples/merge_lora/llama3_full_sft.yaml
+++ b/examples/merge_lora/llama3_full_sft.yaml
@@ -2,7 +2,6 @@
 model_name_or_path: saves/llama3-8b/full/sft
 template: llama3
 trust_remote_code: true
-infer_dtype: bfloat16
 
 ### export
 export_dir: output/llama3_full_sft
diff --git a/src/llamafactory/data/template.py b/src/llamafactory/data/template.py
index 61cb27a1..ccd322c4 100644
--- a/src/llamafactory/data/template.py
+++ b/src/llamafactory/data/template.py
@@ -321,10 +321,11 @@ class Template:
 
         TODO: support function calling.
         """
-        modelfile = f'FROM .\n\nTEMPLATE """{self._get_ollama_template(tokenizer)}"""\n\n'
+        modelfile = "# ollama modelfile auto-generated by llamafactory\n\n"
+        modelfile += f'FROM .\n\nTEMPLATE """{self._get_ollama_template(tokenizer)}"""\n\n'
 
         if self.default_system:
-            modelfile += f'SYSTEM system "{self.default_system}"\n\n'
+            modelfile += f'SYSTEM """{self.default_system}"""\n\n'
 
         for stop_token_id in self.get_stop_token_ids(tokenizer):
             modelfile += f'PARAMETER stop "{tokenizer.convert_ids_to_tokens(stop_token_id)}"\n'
diff --git a/src/llamafactory/train/tuner.py b/src/llamafactory/train/tuner.py
index 23a39774..73800694 100644
--- a/src/llamafactory/train/tuner.py
+++ b/src/llamafactory/train/tuner.py
@@ -22,6 +22,7 @@ from transformers import PreTrainedModel
 from ..data import get_template_and_fix_tokenizer
 from ..extras import logging
 from ..extras.constants import V_HEAD_SAFE_WEIGHTS_NAME, V_HEAD_WEIGHTS_NAME
+from ..extras.misc import infer_optim_dtype
 from ..extras.packages import is_ray_available
 from ..hparams import get_infer_args, get_ray_args, get_train_args, read_args
 from ..model import load_model, load_tokenizer
@@ -117,7 +118,9 @@ def export_model(args: Optional[Dict[str, Any]] = None) -> None:
         setattr(model.config, "torch_dtype", torch.float16)
     else:
         if model_args.infer_dtype == "auto":
-            output_dtype = getattr(model.config, "torch_dtype", torch.float16)
+            output_dtype = getattr(model.config, "torch_dtype", torch.float32)
+            if output_dtype == torch.float32:  # if infer_dtype is auto, try using half precision first
+                output_dtype = infer_optim_dtype(torch.bfloat16)
         else:
             output_dtype = getattr(torch, model_args.infer_dtype)
 
diff --git a/tests/data/test_template.py b/tests/data/test_template.py
index 61923678..9f8fc835 100644
--- a/tests/data/test_template.py
+++ b/tests/data/test_template.py
@@ -123,6 +123,7 @@ def test_ollama_modelfile():
     tokenizer = AutoTokenizer.from_pretrained(TINY_LLAMA)
     template = get_template_and_fix_tokenizer(tokenizer, DataArguments(template="llama3"))
     assert template.get_ollama_modelfile(tokenizer) == (
+        "# ollama modelfile auto-generated by llamafactory\n\n"
         "FROM .\n\n"
         'TEMPLATE """<|begin_of_text|>'
         "{{ if .System }}<|start_header_id|>system<|end_header_id|>\n\n{{ .System }}<|eot_id|>{{ end }}"