diff --git a/src/llmtuner/api/protocol.py b/src/llmtuner/api/protocol.py
index 7a69acb4..3e39fe0b 100644
--- a/src/llmtuner/api/protocol.py
+++ b/src/llmtuner/api/protocol.py
@@ -59,7 +59,7 @@ class ChatCompletionMessage(BaseModel):
 class ChatCompletionRequest(BaseModel):
     model: str
     messages: List[ChatMessage]
-    tools: Optional[list] = []
+    tools: list = []
     do_sample: bool = True
     temperature: Optional[float] = None
     top_p: Optional[float] = None
diff --git a/src/llmtuner/data/preprocess.py b/src/llmtuner/data/preprocess.py
index 60dccefe..c2b87860 100644
--- a/src/llmtuner/data/preprocess.py
+++ b/src/llmtuner/data/preprocess.py
@@ -21,8 +21,11 @@ logger = get_logger(__name__)
 def preprocess_pretrain_dataset(
     examples: Dict[str, List[Any]], tokenizer: "PreTrainedTokenizer", data_args: "DataArguments"
 ) -> Dict[str, List[List[int]]]:
-    # build grouped texts with format `X1 X2 X3 ...`
+    # build grouped texts with format `X1 X2 X3 ...` if packing is enabled
     text_examples = [messages[0]["content"] + tokenizer.eos_token for messages in examples["prompt"]]
+    if not data_args.packing:
+        return tokenizer(text_examples, add_special_tokens=False, max_length=data_args.cutoff_len)
+
     tokenized_examples = tokenizer(text_examples, add_special_tokens=False)
     concatenated_examples = {k: list(chain(*tokenized_examples[k])) for k in tokenized_examples.keys()}
     total_length = len(concatenated_examples[list(concatenated_examples.keys())[0]])
@@ -245,7 +248,7 @@ def get_preprocess_and_print_func(
         preprocess_func = partial(preprocess_pretrain_dataset, tokenizer=tokenizer, data_args=data_args)
         print_function = partial(print_unsupervised_dataset_example, tokenizer=tokenizer)
     elif stage == "sft" and not training_args.predict_with_generate:
-        if data_args.sft_packing:
+        if data_args.packing:
             preprocess_func = partial(
                 preprocess_packed_supervised_dataset, tokenizer=tokenizer, template=template, data_args=data_args
             )
diff --git a/src/llmtuner/data/template.py b/src/llmtuner/data/template.py
index 5f90e105..2a2a9970 100644
--- a/src/llmtuner/data/template.py
+++ b/src/llmtuner/data/template.py
@@ -36,8 +36,8 @@ class Template:
         messages: List[Dict[str, str]],
         system: Optional[str] = None,
         tools: Optional[str] = None,
-        cutoff_len: Optional[int] = 1_000_000,
-        reserved_label_len: Optional[int] = 1,
+        cutoff_len: int = 1_000_000,
+        reserved_label_len: int = 1,
     ) -> Tuple[List[int], List[int]]:
         r"""
         Returns a single pair of token ids representing prompt and response respectively.
@@ -56,8 +56,8 @@ class Template:
         messages: List[Dict[str, str]],
         system: Optional[str] = None,
         tools: Optional[str] = None,
-        cutoff_len: Optional[int] = 1_000_000,
-        reserved_label_len: Optional[int] = 1,
+        cutoff_len: int = 1_000_000,
+        reserved_label_len: int = 1,
     ) -> Sequence[Tuple[List[int], List[int]]]:
         r"""
         Returns multiple pairs of token ids representing prompts and responses respectively.
@@ -207,11 +207,11 @@ def _register_template(
     format_observation: Optional["Formatter"] = None,
     format_tools: Optional["Formatter"] = None,
     format_separator: Optional["Formatter"] = None,
-    default_system: Optional[str] = "",
-    stop_words: Optional[List[str]] = [],
-    efficient_eos: Optional[bool] = False,
-    replace_eos: Optional[bool] = False,
-    force_system: Optional[bool] = False,
+    default_system: str = "",
+    stop_words: List[str] = [],
+    efficient_eos: bool = False,
+    replace_eos: bool = False,
+    force_system: bool = False,
 ) -> None:
     r"""
     Registers a chat template.
@@ -279,9 +279,7 @@ def _jinja_escape(content: str) -> str:
     return content.replace("\n", r"\n").replace("'", r"\'")
 
 
-def _convert_slots_to_jinja(
-    slots: "SLOTS", tokenizer: "PreTrainedTokenizer", placeholder: Optional[str] = "content"
-) -> str:
+def _convert_slots_to_jinja(slots: "SLOTS", tokenizer: "PreTrainedTokenizer", placeholder: str = "content") -> str:
     slot_items = []
     for slot in slots:
         if isinstance(slot, str):
diff --git a/src/llmtuner/extras/ploting.py b/src/llmtuner/extras/ploting.py
index 74d7358c..0e8ad245 100644
--- a/src/llmtuner/extras/ploting.py
+++ b/src/llmtuner/extras/ploting.py
@@ -1,7 +1,7 @@
 import json
 import math
 import os
-from typing import List, Optional
+from typing import List
 
 from transformers.trainer import TRAINER_STATE_NAME
 
@@ -30,7 +30,7 @@ def smooth(scalars: List[float]) -> List[float]:
     return smoothed
 
 
-def plot_loss(save_dictionary: os.PathLike, keys: Optional[List[str]] = ["loss"]) -> None:
+def plot_loss(save_dictionary: os.PathLike, keys: List[str] = ["loss"]) -> None:
     with open(os.path.join(save_dictionary, TRAINER_STATE_NAME), "r", encoding="utf-8") as f:
         data = json.load(f)
 
diff --git a/src/llmtuner/hparams/data_args.py b/src/llmtuner/hparams/data_args.py
index bfc7f3e8..76e6d6da 100644
--- a/src/llmtuner/hparams/data_args.py
+++ b/src/llmtuner/hparams/data_args.py
@@ -78,9 +78,11 @@ class DataArguments:
         default=0.0,
         metadata={"help": "Size of the development set, should be an integer or a float in range `[0,1)`."},
     )
-    sft_packing: bool = field(
-        default=False,
-        metadata={"help": "Packing the questions and answers in the supervised fine-tuning stage."},
+    packing: Optional[bool] = field(
+        default=None,
+        metadata={
+            "help": "Whether or not to pack the sequences in training. Will automatically enable in pre-training."
+        },
     )
     cache_path: Optional[str] = field(
         default=None,
diff --git a/src/llmtuner/hparams/model_args.py b/src/llmtuner/hparams/model_args.py
index a1e4283f..d0e25d9a 100644
--- a/src/llmtuner/hparams/model_args.py
+++ b/src/llmtuner/hparams/model_args.py
@@ -135,7 +135,6 @@ class ModelArguments:
     )
 
     def __post_init__(self):
-        self.aqlm_optimization = None
         self.compute_dtype = None
         self.device_map = None
         self.model_max_length = None
diff --git a/src/llmtuner/hparams/parser.py b/src/llmtuner/hparams/parser.py
index 14cf9bfd..f275a1cb 100644
--- a/src/llmtuner/hparams/parser.py
+++ b/src/llmtuner/hparams/parser.py
@@ -230,7 +230,7 @@ def get_train_args(args: Optional[Dict[str, Any]] = None) -> _TRAIN_CLS:
         model_args.compute_dtype = torch.float16
 
     model_args.model_max_length = data_args.cutoff_len
-    model_args.aqlm_optimization = not training_args.predict_with_generate
+    data_args.packing = data_args.packing if data_args.packing is not None else finetuning_args.stage == "pt"
 
     # Log on each process the small summary:
     logger.info(
@@ -253,7 +253,6 @@ def get_infer_args(args: Optional[Dict[str, Any]] = None) -> _INFER_CLS:
 
     _set_transformers_logging()
     _verify_model_args(model_args, finetuning_args)
-    model_args.aqlm_optimization = False
     model_args.device_map = "auto"
 
     if data_args.template is None:
@@ -267,7 +266,6 @@ def get_eval_args(args: Optional[Dict[str, Any]] = None) -> _EVAL_CLS:
 
     _set_transformers_logging()
     _verify_model_args(model_args, finetuning_args)
-    model_args.aqlm_optimization = True
     model_args.device_map = "auto"
 
     if data_args.template is None:
diff --git a/src/llmtuner/model/loader.py b/src/llmtuner/model/loader.py
index 0760e792..531d3ea3 100644
--- a/src/llmtuner/model/loader.py
+++ b/src/llmtuner/model/loader.py
@@ -1,4 +1,4 @@
-from typing import TYPE_CHECKING, Any, Dict, Optional, Tuple
+from typing import TYPE_CHECKING, Any, Dict, Tuple
 
 from transformers import AutoConfig, AutoModelForCausalLM, AutoTokenizer
 from trl import AutoModelForCausalLMWithValueHead
@@ -52,8 +52,8 @@ def load_model(
     tokenizer: "PreTrainedTokenizer",
     model_args: "ModelArguments",
     finetuning_args: "FinetuningArguments",
-    is_trainable: Optional[bool] = False,
-    add_valuehead: Optional[bool] = False,
+    is_trainable: bool = False,
+    add_valuehead: bool = False,
 ) -> "PreTrainedModel":
     r"""
     Loads pretrained model. Must after load_tokenizer.
@@ -137,8 +137,8 @@ def load_model(
 def load_model_and_tokenizer(
     model_args: "ModelArguments",
     finetuning_args: "FinetuningArguments",
-    is_trainable: Optional[bool] = False,
-    add_valuehead: Optional[bool] = False,
+    is_trainable: bool = False,
+    add_valuehead: bool = False,
 ) -> Tuple["PreTrainedModel", "PreTrainedTokenizer"]:
     r"""
     Loads pretrained model and tokenizer.
diff --git a/src/llmtuner/model/patcher.py b/src/llmtuner/model/patcher.py
index 443a4491..401bdfe0 100644
--- a/src/llmtuner/model/patcher.py
+++ b/src/llmtuner/model/patcher.py
@@ -3,7 +3,7 @@ import os
 import random
 from contextlib import nullcontext
 from types import MethodType
-from typing import TYPE_CHECKING, Any, Dict, List, Optional, Tuple
+from typing import TYPE_CHECKING, Any, Dict, List, Tuple
 
 import torch
 from datasets import load_dataset
@@ -219,7 +219,7 @@ def _configure_quantization(
 
 
 def _prepare_model_for_training(
-    model: "PreTrainedModel", model_args: "ModelArguments", output_layer_name: Optional[str] = "lm_head"
+    model: "PreTrainedModel", model_args: "ModelArguments", output_layer_name: str = "lm_head"
 ) -> None:
     r"""
     Includes:
diff --git a/src/llmtuner/train/dpo/trainer.py b/src/llmtuner/train/dpo/trainer.py
index eb989b19..ed8bf4ce 100644
--- a/src/llmtuner/train/dpo/trainer.py
+++ b/src/llmtuner/train/dpo/trainer.py
@@ -22,7 +22,7 @@ class CustomDPOTrainer(DPOTrainer):
         ftx_gamma: float,
         model: Union["PreTrainedModel", torch.nn.Module],
         ref_model: Optional[Union["PreTrainedModel", torch.nn.Module]] = None,
-        disable_dropout: Optional[bool] = True,
+        disable_dropout: bool = True,
         **kwargs,
     ):
         if disable_dropout:
@@ -95,7 +95,7 @@ class CustomDPOTrainer(DPOTrainer):
         self,
         model: "PreTrainedModel",
         batch: Dict[str, torch.Tensor],
-        train_eval: Optional[Literal["train", "eval"]] = "train",
+        train_eval: Literal["train", "eval"] = "train",
     ) -> Tuple[torch.Tensor, Dict[str, torch.Tensor]]:
         r"""
         Computes the DPO loss and other metrics for the given batch of inputs for train or test.
diff --git a/src/llmtuner/train/ppo/trainer.py b/src/llmtuner/train/ppo/trainer.py
index 2dd61382..a06d7ef1 100644
--- a/src/llmtuner/train/ppo/trainer.py
+++ b/src/llmtuner/train/ppo/trainer.py
@@ -292,7 +292,7 @@ class CustomPPOTrainer(PPOTrainer, Trainer):
         queries: torch.Tensor,
         responses: torch.Tensor,
         model_inputs: dict,
-        return_logits: Optional[bool] = False,
+        return_logits: bool = False,
         response_masks: Optional[torch.Tensor] = None,
     ):
         r"""
diff --git a/src/llmtuner/train/rm/trainer.py b/src/llmtuner/train/rm/trainer.py
index 7d96e7c3..f7e104c8 100644
--- a/src/llmtuner/train/rm/trainer.py
+++ b/src/llmtuner/train/rm/trainer.py
@@ -1,6 +1,6 @@
 import json
 import os
-from typing import TYPE_CHECKING, Dict, List, Optional, Tuple, Union
+from typing import TYPE_CHECKING, Dict, List, Tuple, Union
 
 import torch
 from transformers import Trainer
@@ -26,7 +26,7 @@ class PairwiseTrainer(Trainer):
         self.can_return_loss = True  # override property to return eval_loss
 
     def compute_loss(
-        self, model: "PreTrainedModel", inputs: Dict[str, torch.Tensor], return_outputs: Optional[bool] = False
+        self, model: "PreTrainedModel", inputs: Dict[str, torch.Tensor], return_outputs: bool = False
     ) -> Union[torch.Tensor, Tuple[torch.Tensor, List[torch.Tensor]]]:
         r"""
         Computes pairwise loss. The first n examples are chosen and the last n examples are rejected.
diff --git a/src/llmtuner/train/utils.py b/src/llmtuner/train/utils.py
index 39fb77f4..9d4526a0 100644
--- a/src/llmtuner/train/utils.py
+++ b/src/llmtuner/train/utils.py
@@ -46,7 +46,7 @@ def create_modelcard_and_push(
 
 
 def create_ref_model(
-    model_args: "ModelArguments", finetuning_args: "FinetuningArguments", add_valuehead: Optional[bool] = False
+    model_args: "ModelArguments", finetuning_args: "FinetuningArguments", add_valuehead: bool = False
 ) -> Union["PreTrainedModel", "AutoModelForCausalLMWithValueHead"]:
     r"""
     Creates reference model for PPO/DPO training. Evaluation mode is not supported.
diff --git a/src/llmtuner/webui/chatter.py b/src/llmtuner/webui/chatter.py
index 5ecb8159..d149ca26 100644
--- a/src/llmtuner/webui/chatter.py
+++ b/src/llmtuner/webui/chatter.py
@@ -18,9 +18,7 @@ if TYPE_CHECKING:
 
 
 class WebChatModel(ChatModel):
-    def __init__(
-        self, manager: "Manager", demo_mode: Optional[bool] = False, lazy_init: Optional[bool] = True
-    ) -> None:
+    def __init__(self, manager: "Manager", demo_mode: bool = False, lazy_init: bool = True) -> None:
         self.manager = manager
         self.demo_mode = demo_mode
         self.engine: Optional["BaseEngine"] = None
diff --git a/src/llmtuner/webui/common.py b/src/llmtuner/webui/common.py
index 3a968110..961d6f0d 100644
--- a/src/llmtuner/webui/common.py
+++ b/src/llmtuner/webui/common.py
@@ -104,10 +104,12 @@ def load_dataset_info(dataset_dir: str) -> Dict[str, Dict[str, Any]]:
         return {}
 
 
-def list_dataset(
-    dataset_dir: Optional[str] = None, training_stage: Optional[str] = list(TRAINING_STAGES.keys())[0]
-) -> Dict[str, Any]:
+def list_dataset(dataset_dir: str = None, training_stage: str = list(TRAINING_STAGES.keys())[0]) -> Dict[str, Any]:
     dataset_info = load_dataset_info(dataset_dir if dataset_dir is not None else DEFAULT_DATA_DIR)
     ranking = TRAINING_STAGES[training_stage] in ["rm", "dpo"]
     datasets = [k for k, v in dataset_info.items() if v.get("ranking", False) == ranking]
     return gr.update(value=[], choices=datasets)
+
+
+def autoset_packing(training_stage: str = list(TRAINING_STAGES.keys())[0]) -> Dict[str, Any]:
+    return gr.update(value=(TRAINING_STAGES[training_stage] == "pt"))
diff --git a/src/llmtuner/webui/components/chatbot.py b/src/llmtuner/webui/components/chatbot.py
index bd900c93..bf5bb66a 100644
--- a/src/llmtuner/webui/components/chatbot.py
+++ b/src/llmtuner/webui/components/chatbot.py
@@ -1,4 +1,4 @@
-from typing import TYPE_CHECKING, Dict, Optional, Tuple
+from typing import TYPE_CHECKING, Dict, Tuple
 
 import gradio as gr
 
@@ -14,7 +14,7 @@ if TYPE_CHECKING:
 
 
 def create_chat_box(
-    engine: "Engine", visible: Optional[bool] = False
+    engine: "Engine", visible: bool = False
 ) -> Tuple["Block", "Component", "Component", Dict[str, "Component"]]:
     with gr.Box(visible=visible) as chat_box:
         chatbot = gr.Chatbot()
diff --git a/src/llmtuner/webui/components/top.py b/src/llmtuner/webui/components/top.py
index b0e56bee..d8b49588 100644
--- a/src/llmtuner/webui/components/top.py
+++ b/src/llmtuner/webui/components/top.py
@@ -1,4 +1,4 @@
-from typing import TYPE_CHECKING, Dict
+from typing import TYPE_CHECKING, Dict, Tuple
 
 import gradio as gr
 
@@ -12,7 +12,7 @@ if TYPE_CHECKING:
     from gradio.components import Component
 
 
-def create_top() -> Dict[str, "Component"]:
+def create_top() -> Tuple["gr.Dropdown", Dict[str, "Component"]]:
     available_models = list(SUPPORTED_MODELS.keys()) + ["Custom"]
 
     with gr.Row():
@@ -44,7 +44,7 @@ def create_top() -> Dict[str, "Component"]:
 
     refresh_btn.click(list_adapters, [model_name, finetuning_type], [adapter_path], queue=False)
 
-    return dict(
+    return lang, dict(
         lang=lang,
         model_name=model_name,
         model_path=model_path,
diff --git a/src/llmtuner/webui/components/train.py b/src/llmtuner/webui/components/train.py
index 25a518b9..0725f5eb 100644
--- a/src/llmtuner/webui/components/train.py
+++ b/src/llmtuner/webui/components/train.py
@@ -4,7 +4,7 @@ import gradio as gr
 from transformers.trainer_utils import SchedulerType
 
 from ...extras.constants import TRAINING_STAGES
-from ..common import DEFAULT_DATA_DIR, list_adapters, list_dataset
+from ..common import DEFAULT_DATA_DIR, autoset_packing, list_adapters, list_dataset
 from ..components.data import create_preview_box
 from ..utils import gen_plot
 
@@ -78,7 +78,7 @@ def create_train_tab(engine: "Engine") -> Dict[str, "Component"]:
 
         with gr.Row():
             resize_vocab = gr.Checkbox()
-            sft_packing = gr.Checkbox()
+            packing = gr.Checkbox()
             upcast_layernorm = gr.Checkbox()
             use_llama_pro = gr.Checkbox()
             shift_attn = gr.Checkbox()
@@ -91,7 +91,7 @@ def create_train_tab(engine: "Engine") -> Dict[str, "Component"]:
             neftune_alpha,
             optim,
             resize_vocab,
-            sft_packing,
+            packing,
             upcast_layernorm,
             use_llama_pro,
             shift_attn,
@@ -106,7 +106,7 @@ def create_train_tab(engine: "Engine") -> Dict[str, "Component"]:
             neftune_alpha=neftune_alpha,
             optim=optim,
             resize_vocab=resize_vocab,
-            sft_packing=sft_packing,
+            packing=packing,
             upcast_layernorm=upcast_layernorm,
             use_llama_pro=use_llama_pro,
             shift_attn=shift_attn,
@@ -166,7 +166,7 @@ def create_train_tab(engine: "Engine") -> Dict[str, "Component"]:
         [engine.manager.get_elem_by_name("top.model_name"), engine.manager.get_elem_by_name("top.finetuning_type")],
         [reward_model],
         queue=False,
-    )
+    ).then(autoset_packing, [training_stage], [packing], queue=False)
 
     input_elems.update({dpo_beta, dpo_ftx, reward_model})
     elem_dict.update(dict(rlhf_tab=rlhf_tab, dpo_beta=dpo_beta, dpo_ftx=dpo_ftx, reward_model=reward_model))
diff --git a/src/llmtuner/webui/engine.py b/src/llmtuner/webui/engine.py
index fe8a02ae..fb04ca05 100644
--- a/src/llmtuner/webui/engine.py
+++ b/src/llmtuner/webui/engine.py
@@ -1,4 +1,4 @@
-from typing import Any, Dict, Generator, Optional
+from typing import Any, Dict, Generator
 
 import gradio as gr
 from gradio.components import Component  # cannot use TYPE_CHECKING here
@@ -12,7 +12,7 @@ from .utils import get_time
 
 
 class Engine:
-    def __init__(self, demo_mode: Optional[bool] = False, pure_chat: Optional[bool] = False) -> None:
+    def __init__(self, demo_mode: bool = False, pure_chat: bool = False) -> None:
         self.demo_mode = demo_mode
         self.pure_chat = pure_chat
         self.manager = Manager()
diff --git a/src/llmtuner/webui/interface.py b/src/llmtuner/webui/interface.py
index b84fa948..a1f4d53f 100644
--- a/src/llmtuner/webui/interface.py
+++ b/src/llmtuner/webui/interface.py
@@ -1,5 +1,3 @@
-from typing import Optional
-
 import gradio as gr
 from transformers.utils.versions import require_version
 
@@ -19,7 +17,7 @@ from .engine import Engine
 require_version("gradio>=3.38.0,<4.0.0", 'To fix: pip install "gradio>=3.38.0,<4.0.0"')
 
 
-def create_ui(demo_mode: Optional[bool] = False) -> gr.Blocks:
+def create_ui(demo_mode: bool = False) -> gr.Blocks:
     engine = Engine(demo_mode=demo_mode, pure_chat=False)
 
     with gr.Blocks(title="LLaMA Board", css=CSS) as demo:
@@ -31,8 +29,7 @@ def create_ui(demo_mode: Optional[bool] = False) -> gr.Blocks:
             )
             gr.DuplicateButton(value="Duplicate Space for private use", elem_classes="duplicate-button")
 
-        engine.manager.all_elems["top"] = create_top()
-        lang: "gr.Dropdown" = engine.manager.get_elem_by_name("top.lang")
+        lang, engine.manager.all_elems["top"] = create_top()
 
         with gr.Tab("Train"):
             engine.manager.all_elems["train"] = create_train_tab(engine)
diff --git a/src/llmtuner/webui/locales.py b/src/llmtuner/webui/locales.py
index adc85a82..4f329e8e 100644
--- a/src/llmtuner/webui/locales.py
+++ b/src/llmtuner/webui/locales.py
@@ -480,18 +480,18 @@ LOCALES = {
             "info": "更改分词器词表和嵌入层的大小。",
         },
     },
-    "sft_packing": {
+    "packing": {
         "en": {
             "label": "Pack sequences",
-            "info": "Pack sequences into samples of fixed length in supervised fine-tuning.",
+            "info": "Pack sequences into samples of fixed length.",
         },
         "ru": {
             "label": "Упаковка последовательностей",
-            "info": "Упаковка последовательностей в образцы фиксированной длины при контролируемой тонкой настройке.",
+            "info": "Упаковка последовательностей в образцы фиксированной длины.",
         },
         "zh": {
             "label": "序列打包",
-            "info": "在指令监督微调时将序列打包为等长样本。",
+            "info": "将序列打包为等长样本。",
         },
     },
     "upcast_layernorm": {
diff --git a/src/llmtuner/webui/runner.py b/src/llmtuner/webui/runner.py
index 89731fa9..1d5396a9 100644
--- a/src/llmtuner/webui/runner.py
+++ b/src/llmtuner/webui/runner.py
@@ -2,7 +2,7 @@ import logging
 import os
 import time
 from threading import Thread
-from typing import TYPE_CHECKING, Any, Dict, Generator, Optional, Tuple
+from typing import TYPE_CHECKING, Any, Dict, Generator, Tuple
 
 import gradio as gr
 import transformers
@@ -25,7 +25,7 @@ if TYPE_CHECKING:
 
 
 class Runner:
-    def __init__(self, manager: "Manager", demo_mode: Optional[bool] = False) -> None:
+    def __init__(self, manager: "Manager", demo_mode: bool = False) -> None:
         self.manager = manager
         self.demo_mode = demo_mode
         """ Resume """
@@ -136,7 +136,7 @@ class Runner:
             neftune_noise_alpha=get("train.neftune_alpha") or None,
             optim=get("train.optim"),
             resize_vocab=get("train.resize_vocab"),
-            sft_packing=get("train.sft_packing"),
+            packing=get("train.packing"),
             upcast_layernorm=get("train.upcast_layernorm"),
             use_llama_pro=get("train.use_llama_pro"),
             shift_attn=get("train.shift_attn"),