update create_optimizer for updated api

* upgrade transformers to 5.1.0 and torchao to 0.16.0

* upgrade trl for parity

* handle trl api changes

* orpo doesn't have max_prompt_len to check anymore

* cpoconfig doesn't take max_prompt_length and fix cpu offload

* slow fsdp1 test

* triton min 3.4.0 and liger to 0.7.0

* use transformers main for now for zero3 fix

* handle group_by_length change

* fix changes upstream

* mark skip flaky test

* use transformers latest release 5.2.0

requirements.txt

@@ -2,21 +2,21 @@
 
 # START section of dependencies that don't install on Darwin/MacOS
 bitsandbytes==0.49.1
-triton>=3.0.0
+triton>=3.4.0
 mamba-ssm==1.2.0.post1
 xformers>=0.0.23.post1
-liger-kernel==0.6.4
+liger-kernel==0.7.0
 # END section
 
 packaging==26.0
 huggingface_hub>=1.1.7
 peft>=0.18.1
 tokenizers>=0.22.1
-transformers==5.0.0
+transformers @ git+https://github.com/winglian/transformers.git@refactor-inner-training-loop-reorder-only
 accelerate==1.12.0
 datasets==4.5.0
 deepspeed>=0.18.3
-trl==0.27.1
+trl==0.28.0
 hf_xet==1.2.0
 kernels==0.11.5
 
@@ -63,7 +63,7 @@ langdetect==1.0.9
 immutabledict==4.2.0
 antlr4-python3-runtime==4.13.2
 
-torchao==0.13.0
+torchao==0.16.0
 openenv-core==0.1.0
 schedulefree==1.4.1
 

src/axolotl/core/builders/causal.py

@@ -246,7 +246,8 @@ class HFCausalTrainerBuilder(TrainerBuilderBase):
             ddp_find_unused_parameters
         )
 
-        training_arguments_kwargs["group_by_length"] = self.cfg.group_by_length
+        if self.cfg.group_by_length:
+            training_arguments_kwargs["train_sampling_strategy"] = "group_by_length"
         training_arguments_kwargs["curriculum_sampling"] = self.cfg.curriculum_sampling
 
         training_arguments_kwargs["sample_packing"] = bool(self.cfg.sample_packing)

src/axolotl/core/builders/rl.py

@@ -11,7 +11,6 @@ from axolotl.core.trainers import (
 )
 from axolotl.core.trainers.dpo import DPOStrategy
 from axolotl.core.trainers.dpo.args import AxolotlDPOConfig
-from axolotl.core.trainers.grpo import GRPOStrategy
 from axolotl.integrations.base import PluginManager
 from axolotl.loaders.utils import ensure_dtype
 from axolotl.utils.callbacks.qat import QATCallback
@@ -53,6 +52,8 @@ class HFRLTrainerBuilder(TrainerBuilderBase):
         trainer_cls_args = [self.model]
 
         if self.cfg.rl in {RLType.GRPO, RLType.GDPO}:
+            from axolotl.core.trainers.grpo import GRPOStrategy
+
             trainer_cls = GRPOStrategy.get_trainer_class(
                 sequence_parallel=self.cfg.context_parallel_size > 1
             )
@@ -133,21 +134,17 @@ class HFRLTrainerBuilder(TrainerBuilderBase):
             if self.cfg.cpo_alpha is not None:
                 training_args_kwargs["cpo_alpha"] = self.cfg.cpo_alpha
 
-            # Handle when max_prompt_length == max_length from defaults
+            blocklist_args_kwargs.append("max_prompt_length")
-            # CPOTrainer requires strictly less than
-            if (
-                training_args_kwargs["max_prompt_length"]
-                == training_args_kwargs["max_length"]
-            ):
-                training_args_kwargs["max_prompt_length"] -= 1
 
         elif self.cfg.rl is RLType.ORPO:
             training_args_cls = AxolotlORPOConfig
 
+            blocklist_args_kwargs.append("max_prompt_length")
+
         elif self.cfg.rl is RLType.KTO:
             training_args_cls = AxolotlKTOConfig
             # KTOConfig in TRL >= 0.27.0 no longer accepts max_prompt_length
-            blocklist_args_kwargs = ["max_prompt_length"]
+            blocklist_args_kwargs.append("max_prompt_length")
 
             training_args_kwargs["desirable_weight"] = (
                 self.cfg.kto_desirable_weight or 1.0
@@ -157,6 +154,8 @@ class HFRLTrainerBuilder(TrainerBuilderBase):
             )
 
         elif self.cfg.rl in {RLType.GRPO, RLType.GDPO}:
+            from axolotl.core.trainers.grpo import GRPOStrategy
+
             training_args_cls = GRPOStrategy.get_training_args_class()
             training_args_kwargs.update(GRPOStrategy.set_training_args_kwargs(self.cfg))
             blocklist_args_kwargs = GRPOStrategy.get_blocklist_args_kwargs()

src/axolotl/core/trainers/dpo/trainer.py

@@ -57,16 +57,18 @@ class AxolotlDPOTrainer(
     def tokenize_row(
         features,
         processing_class,
-        max_prompt_length,
+        max_prompt_length: int | None = None,
-        max_completion_length,
+        max_completion_length: int | None = None,
-        add_special_tokens,
+        add_special_tokens: bool = True,
+        is_chat: bool = False,
     ) -> Dict:
         res = DPOTrainer.tokenize_row(
             features,
             processing_class,
-            max_prompt_length,
+            max_prompt_length=max_prompt_length,
-            max_completion_length,
+            max_completion_length=max_completion_length,
-            add_special_tokens,
+            add_special_tokens=add_special_tokens,
+            is_chat=is_chat,
         )
         # fix when the tokenizer doesn't have a bos_token_id, e.g. Qwen
         if processing_class.bos_token is None and res["prompt_input_ids"][0] is None:

src/axolotl/core/trainers/mixins/optimizer.py

@@ -104,7 +104,7 @@ class OptimizerMixin(Trainer):
 
         return optimizer_grouped_parameters
 
-    def create_optimizer(self):
+    def create_optimizer(self, model=None):
         if (
             self.args.loraplus_lr_ratio is None
             and self.args.embedding_lr_scale is None
@@ -112,9 +112,9 @@ class OptimizerMixin(Trainer):
             and self.args.lr_groups is None
             and self.optimizer_cls_and_kwargs is None
         ):
-            return super().create_optimizer()
+            return super().create_optimizer(model=model)
 
-        opt_model = self.model_wrapped if is_sagemaker_mp_enabled() else self.model
+        opt_model = self.model if model is None else model
 
         if (
             not self.optimizer

src/axolotl/loaders/patch_manager.py

@@ -10,6 +10,7 @@ from functools import cached_property
 import addict
 import transformers
 from transformers import PretrainedConfig, PreTrainedModel
+from transformers.modeling_flash_attention_utils import is_flash_attn_available
 
 from axolotl.integrations.base import PluginManager
 from axolotl.monkeypatch.multipack import (
@@ -500,6 +501,7 @@ class PatchManager:
             and not self.cfg.trust_remote_code
             and not self.cfg.gptq
             and self.cfg.flash_attention
+            and is_flash_attn_available()
             and not self.inference
         ):
             # TODO(MengqingCao): split these patches separately

src/axolotl/monkeypatch/gradient_checkpointing/offload_cpu.py

@@ -59,7 +59,12 @@ class CPU_Offloaded_Gradient_Checkpointer(torch.autograd.Function):
         hidden_states = hidden_states.to("cuda", non_blocking=True).detach()
         hidden_states.requires_grad = True
         with torch.enable_grad():
-            (output,) = ctx.forward_function(hidden_states, *ctx.args)
+            output = ctx.forward_function(hidden_states, *ctx.args)
+            # Newer HF models (e.g. Qwen3MoE) using GradientCheckpointingLayer
+            # return a plain tensor, not a tuple.  Older models return tuples
+            # like (hidden_states, present_kv, ...).  Unwrap if needed.
+            if isinstance(output, (tuple, list)):
+                (output,) = output
         torch.autograd.backward(output, dY)
         return (
             None,

src/axolotl/monkeypatch/transformers/trainer_loss_calc.py

@@ -28,8 +28,12 @@ PATCHED_EVAL_CODE = {
     "array": 'metrics[f"{metric_key_prefix}_loss"] = np.nanmean(all_losses).item()',
 }
 
-ORIGINAL_MAYBE_CODE = "tr_loss_scalar = self._nested_gather(tr_loss).mean().item()"
+ORIGINAL_MAYBE_CODE = (
-PATCHED_MAYBE_CODE = "tr_loss_scalar = self._nested_gather(tr_loss).nanmean().item()"
+    "tr_loss_scalar = nested_gather(tr_loss, self.args.parallel_mode).mean().item()"
+)
+PATCHED_MAYBE_CODE = (
+    "tr_loss_scalar = nested_gather(tr_loss, self.args.parallel_mode).nanmean().item()"
+)
 
 
 def check_evaluation_loop_is_patchable() -> bool:

src/axolotl/utils/schemas/config.py

@@ -446,7 +446,16 @@ class AxolotlInputConfig(
         },
     )
 
-    unfrozen_parameters: list[str] | None = None
+    unfrozen_parameters: list[str] | None = Field(
+        default=None,
+        json_schema_extra={
+            "description": "List of regex patterns for parameter names to keep unfrozen. "
+            "All other parameters will be frozen via requires_grad=False. "
+            "Note: range-based patterns (e.g. embed_tokens.weight$[:32000]) use gradient "
+            "zeroing rather than a true freeze, so weight decay will still apply to the "
+            "frozen portion and optimizer states are allocated for the full parameter."
+        },
+    )
 
     sequence_len: int = Field(
         default=512,

tests/core/test_builders.py

@@ -300,7 +300,6 @@ class TestHFRLTrainerBuilder:
         self._test_common_training_arguments(training_arguments, rl=orpo_cfg.rl)
         # ORPO specific
         assert training_arguments.beta == 0.1  # maps from orpo_alpha
-        assert training_arguments.max_prompt_length == 512
 
     def test_kto_training_arguments(self, kto_cfg, model, tokenizer):
         builder = HFRLTrainerBuilder(kto_cfg, model, tokenizer)

tests/e2e/multigpu/test_fsdp1.py

@@ -186,6 +186,7 @@ class TestFSDP1:
 
         verify_training_success(temp_dir)
 
+    @pytest.mark.skip(reason="slow test, deprecate fsdp1 asap")
     def test_dpo_fft(self, temp_dir):
         cfg = DictDefault(
             {

tests/e2e/multigpu/test_fsdp2.py

@@ -365,6 +365,7 @@ class TestFSDP2:
 
         verify_training_success(temp_dir)
 
+    @pytest.mark.skip(reason="slow test w cu129 + torch 2.9.1 + py3.12")
     @require_torch_2_7_0
     def test_dpo_fft(self, temp_dir):
         cfg = DictDefault(

tests/prompt_strategies/test_chat_templates.py

@@ -115,6 +115,9 @@ class TestAssistantChatTemplateLlama3:
 
     def test_phi35(self, phi35_tokenizer, assistant_dataset):
         LOG.info("Testing phi-3.5 with assistant dataset")
+        assert "LlamaTokenizer" in phi35_tokenizer.__class__.__name__, (
+            "phi35 tokenizer should be a LlamaTokenizer"
+        )
         strategy = ChatTemplateStrategy(
             ChatTemplatePrompter(
                 phi35_tokenizer,
@@ -140,13 +143,13 @@ class TestAssistantChatTemplateLlama3:
         # fmt: off
         expected_input_ids = [
             32010,  # user
-            22172, 32007,  # user eot
+            12199, 32007,  # user eot
             32001,  # assistant
-            22172, 32007,  # assistant eot
+            12199, 32007,  # assistant eot
             32010,  # user
-            1781, 26966, 32007,  # user eot
+            16773, 26966, 32007,  # user eot
             32001,  # assistant
-            1781, 26966, 32007,  # assistant eot
+            16773, 26966, 32007,  # assistant eot
         ]
         expected_labels = [
             -100,  # user
@@ -156,7 +159,7 @@ class TestAssistantChatTemplateLlama3:
             -100,  # user
             -100, -100, -100,  # user eot
             -100,  # assistant
-            1781, 26966, 32007,  # assistant eot
+            16773, 26966, 32007,  # assistant eot
         ]
         # fmt: on
         LOG.debug(f"Expected input_ids: {expected_input_ids}")

tests/test_tokenizers.py

@@ -84,7 +84,8 @@ class TestTokenizers:
             }
         )
         tokenizer = load_tokenizer(cfg)
-        assert tokenizer("<|im_start|>user")["input_ids"] == [1, 32000, 1404]
+        assert "LlamaTokenizer" in tokenizer.__class__.__name__
+        assert tokenizer("<|im_start|>user")["input_ids"] == [1, 32000, 1792]
         assert len(tokenizer) == 32001
 
         # ensure reloading the tokenizer again from cfg results in same vocab length