Merge branch 'main' into flx_attn_support

* bumping TRL version

* apply upstream fixes to our custom fix

---------

Co-authored-by: Wing Lian <wing@axolotl.ai>

docs/config.qmd

@@ -407,7 +407,10 @@ save_total_limit: # Checkpoints saved at a time
 max_steps:
 
 # bool of whether to include tokens trainer per second in the training metrics. This iterates over the entire dataset once, so it takes some time.
-include_tokens_per_second:
+include_tokens_per_second: # Optional[bool]
+
+# whether to find batch size that fits in memory. Passed to underlying transformers Trainer
+auto_find_batch_size: # Optional[bool]
 
 eval_table_size: # Approximate number of predictions sent to wandb depending on batch size. Enabled above 0. Default is 0
 eval_max_new_tokens: # Total number of tokens generated for predictions sent to wandb. Default is 128

requirements.txt

@@ -13,12 +13,12 @@ liger-kernel==0.5.2
 packaging==23.2
 
 peft==0.14.0
-transformers==4.48.3
+transformers==4.49.0
 tokenizers>=0.21.0
 accelerate==1.3.0
 datasets==3.2.0
 deepspeed==0.16.1
-trl==0.15.0
+trl==0.15.1
 
 optimum==1.16.2
 hf_transfer

src/axolotl/core/trainer_builder.py

@@ -831,7 +831,9 @@ class HFCausalTrainerBuilder(TrainerBuilderBase):
             if "max_length" in kwargs:
                 kwargs.pop("max_length")
         elif use_batch_sampler_collator:
-            if self.cfg.model_config_type in SUPPORTED_MULTIPACK_MODEL_TYPES:
+            if self.cfg.flex_attention is True:
+                collator = V2BatchSamplerDataCollatorForSeq2Seq
+            elif self.cfg.model_config_type in SUPPORTED_MULTIPACK_MODEL_TYPES:
                 collator = V2BatchSamplerDataCollatorForSeq2Seq
             elif (
                 self.cfg.model_config_type in ["llama"]

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

@@ -78,7 +78,6 @@ class AxolotlGRPOTrainer(SchedulerMixin, GRPOTrainer):
             if is_peft_model(unwrapped_model):
                 unwrapped_model.merge_adapter()
                 state_dict = unwrapped_model.state_dict()
-                unwrapped_model.unmerge_adapter()
                 # Remove base_model and base_layer prefixes
                 state_dict = {
                     k.removeprefix("base_model.model.")
@@ -100,8 +99,10 @@ class AxolotlGRPOTrainer(SchedulerMixin, GRPOTrainer):
                 }
             else:
                 state_dict = unwrapped_model.state_dict()
-        if self.accelerator.is_main_process:
-            llm_model = (
-                self.llm.llm_engine.model_executor.driver_worker.model_runner.model
-            )
-            llm_model.load_weights(state_dict.items())
+            if self.accelerator.is_main_process:
+                llm_model = (
+                    self.llm.llm_engine.model_executor.driver_worker.model_runner.model
+                )
+                llm_model.load_weights(state_dict.items())
+            if is_peft_model(unwrapped_model):
+                unwrapped_model.unmerge_adapter()

src/axolotl/monkeypatch/relora.py

@@ -127,6 +127,8 @@ class ReLoRACallback(TrainerCallback):
         optimizer: torch.optim.Optimizer,
         **_kwargs,
     ):
+        if not optimizer:
+            optimizer = state.optimizer
         if state.global_step > 0 and state.global_step % self.relora_steps == 0:
             checkpoint_folder = os.path.join(
                 args.output_dir,

src/axolotl/monkeypatch/utils.py

@@ -95,6 +95,103 @@ def get_cu_seqlens(attn_mask):
     return torch.stack(results).to(dtype=torch.int32), torch.stack(max_seq_lens)
 
 
+def get_packed_mask_from_pos_ids(position_ids):
+    if len(position_ids.shape) == 1:
+        position_ids = position_ids.unsqueeze(0)
+
+    device = position_ids.device
+    results = []
+
+    for i, row in enumerate(position_ids):
+        # Count the number of consecutive zeros from the right side
+        padding_length = (row == 0).int().flip(dims=[0]).cumprod(dim=0).sum().item()
+
+        # Adjust the row to exclude padding
+        adjusted_row = row[:-padding_length] if padding_length else row.clone()
+
+        # Find where the position resets to 0 (indicating a new sequence)
+        seq_starts = torch.cat(
+            [
+                torch.tensor([True], dtype=torch.bool, device=device),
+                adjusted_row[1:] == 0,
+            ]
+        )
+        # Get the indices where the sequence starts
+        start_indices = torch.cat(
+            [
+                torch.nonzero(seq_starts).unbind(dim=1)[0],
+                torch.tensor([len(adjusted_row)], dtype=torch.int32, device=device),
+            ]
+        )
+        # Calculate the sequence lengths
+        seq_lengths = start_indices[1:] - start_indices[:-1]
+        # Append the padding length to the sequence lengths
+        doc_mask = torch.ones(len(row), dtype=torch.int32, device=device)
+        for i, seq_len in enumerate(seq_lengths):
+            start_id = start_indices[i]
+            doc_mask[start_id : start_id + seq_len] = (
+                (i+1) * doc_mask[start_id : start_id + seq_len]
+            )
+        if padding_length:
+            doc_mask[len(adjusted_row) :] = 0 * doc_mask[len(adjusted_row) :]
+
+        results.append(doc_mask)
+
+    return torch.stack(results)
+
+
+def get_seqlens_from_pos_ids(position_ids):
+    """generate a sequence length set using pos ids for doc mask creation in flex attention"""
+    if len(position_ids.shape) == 1:
+        position_ids = position_ids.unsqueeze(0)
+    max_seq_len = position_ids.shape[1]
+
+    device = position_ids.device
+    results = []
+    totalseqlens = []
+
+    for row in position_ids:
+        # Count the number of consecutive zeros from the right side
+        padding_length = (row == 0).int().flip(dims=[0]).cumprod(dim=0).sum().item()
+
+        # Adjust the row to exclude padding
+        adjusted_row = row[:-padding_length] if padding_length else row.clone()
+
+        # Find where the position resets to 0 (indicating a new sequence)
+        seq_starts = torch.cat(
+            [
+                torch.tensor([True], dtype=torch.bool, device=device),
+                adjusted_row[1:] == 0,
+            ]
+        )
+        # Get the indices where the sequence starts
+        start_indices = torch.cat(
+            [
+                torch.nonzero(seq_starts).unbind(dim=1)[0],
+                torch.tensor([len(adjusted_row)], dtype=torch.int32, device=device),
+            ]
+        )
+        # Calculate the sequence lengths
+        seq_lengths = start_indices[1:] - start_indices[:-1]
+        # Append the padding length to the sequence lengths
+        if padding_length:
+            seq_lengths = torch.cat(
+                [
+                    seq_lengths,
+                    torch.tensor(
+                        [len(row) - torch.sum(seq_lengths)],
+                        dtype=torch.int32,
+                        device=device,
+                    ),
+                ]
+            )
+
+        results.append(seq_lengths)
+        totalseqlens.append(len(adjusted_row))
+
+    return results, torch.tensor(totalseqlens, dtype=torch.int32, device=device)
+
+
 def get_cu_seqlens_from_pos_ids(position_ids):
     """generate a cumulative sequence length mask for flash attention using pos ids"""
     if len(position_ids.shape) == 1:
@@ -176,7 +273,10 @@ def mask_2d_to_4d(
     when they attend to each other within that sequence.
     This expansion transforms the mask to lower triangular form to prevent future peeking.
     """
-    bsz, src_len = mask.size()
+
+    if len(mask.size()) == 4:
+        return mask
+    bsz, src_len = int(mask.size()[0]), int(mask.size()[1])
     tgt_len = tgt_len if tgt_len is not None else src_len
 
     mask = mask.unsqueeze(1).unsqueeze(2)

src/axolotl/prompt_strategies/chat_template.py

@@ -272,8 +272,7 @@ class ChatTemplateStrategy(PromptTokenizingStrategy):
                 dict(zip(feature_names, row))
             )
             for key, val in tokenized_prompt.items():
-                for i in range(0, len(val), self.sequence_len):
-                    res[key].append(val[i : i + self.sequence_len])
+                res[key].append(val)
 
         # If there are no examples left, return an empty dictionary
         if not res:

src/axolotl/utils/config/models/input/v0_4_1/__init__.py

@@ -342,6 +342,7 @@ class LoraConfig(BaseModel):
     peft_use_dora: Optional[bool] = None
     peft_use_rslora: Optional[bool] = None
     peft_layer_replication: Optional[List[Tuple[int, int]]] = None
+    peft_init_lora_weights: Optional[Union[bool, str]] = None
 
     qlora_sharded_model_loading: Optional[bool] = Field(
         default=False,
@@ -822,6 +823,7 @@ class AxolotlInputConfig(
     xformers_attention: Optional[bool] = None
     sdp_attention: Optional[bool] = None
     s2_attention: Optional[bool] = None
+    flex_attention: Optional[bool] = None
     flash_attention: Optional[bool] = None
     flash_attn_cross_entropy: Optional[bool] = None
     flash_attn_rms_norm: Optional[bool] = None
@@ -1788,6 +1790,26 @@ class AxolotlConfigWCapabilities(AxolotlInputConfig):
                 )
         return data
 
+    @model_validator(mode="before")
+    @classmethod
+    def check_flex_torch_version(cls, data):
+        if (data.get("flex_attention") is not None) and (
+            data.get("flex_attention") is True
+        ):
+            env_capabilities = data.get("env_capabilities", {})
+            torch_version = env_capabilities.get("torch_version")
+
+            if torch_version is None:
+                import torch
+
+                torch_version = str(torch.__version__).split("+", maxsplit=1)[0]
+
+            if version.parse(torch_version) < version.parse("2.5.1"):
+                raise ValueError(
+                    "Flex attention is not supported on torch version < 2.5.1"
+                )
+        return data
+
     @model_validator(mode="before")
     @classmethod
     def check_torch_compile_auto(cls, data):

src/axolotl/utils/data/utils.py

@@ -172,10 +172,11 @@ def drop_long_seq_in_dataset(dataset: Dataset, cfg: DictDefault):
     )
 
     try:
-        min_input_len = np.min(get_dataset_lengths(dataset))
-        LOG.debug(f"min_input_len: {min_input_len}")
-        max_input_len = np.max(get_dataset_lengths(dataset))
-        LOG.debug(f"max_input_len: {max_input_len}")
+        ds_lengths = get_dataset_lengths(dataset, from_arrow=True)
+        min_input_len = np.min(ds_lengths)
+        LOG.info(f"min_input_len: {min_input_len}")
+        max_input_len = np.max(ds_lengths)
+        LOG.info(f"max_input_len: {max_input_len}")
     except AttributeError:
         pass
 

src/axolotl/utils/models.py

@@ -403,7 +403,7 @@ class ModelLoader:
 
         if (
             self.cfg.model_config_type in SUPPORTED_MULTIPACK_MODEL_TYPES
-            and self.cfg.flash_attention
+            and (self.cfg.flash_attention or self.cfg.flex_attention)
             and self.cfg.sample_packing
         ):
             if "auto_map" in self.model_config:
@@ -707,7 +707,13 @@ class ModelLoader:
         """
         sample packing uses custom FA2 patch
         """
-        if self.cfg.flash_attention:
+
+        if self.cfg.flex_attention:
+            self.model_kwargs["attn_implementation"] = "flex_attention"
+            self.model_config._attn_implementation = (  # pylint: disable=protected-access
+                "flex_attention"
+            )
+        elif self.cfg.flash_attention:
             if not self.cfg.sample_packing and self.cfg.s2_attention:
                 pass
             self.model_kwargs["attn_implementation"] = "flash_attention_2"
@@ -1113,7 +1119,7 @@ class ModelLoader:
         should_convert = (
             # LlamaRMSNorm layers are in fp32 after kbit_training or full finetune, so we need to
             # convert them back to fp16/bf16 for flash-attn compatibility.
-            ((needs_fa2_dtype or self.cfg.flash_attention) and not qlora_fsdp)
+            ((needs_fa2_dtype or self.cfg.flash_attention or self.cfg.flex_attention) and not qlora_fsdp)
             or self.cfg.cut_cross_entropy  # Cut cross entropy requires embedding layers to be in fp16/bf16 for backward pass
         )
 
@@ -1321,6 +1327,8 @@ def load_lora(model, cfg, inference=False, config_only=False):
     if loftq_bits:
         lora_config_kwargs["loftq_config"] = LoftQConfig(loftq_bits=loftq_bits)
         lora_config_kwargs["init_lora_weights"] = "loftq"
+    if cfg.peft_init_lora_weights:
+        lora_config_kwargs["init_lora_weights"] = cfg.peft_init_lora_weights
     if cfg.peft_use_dora:
         lora_config_kwargs["use_dora"] = cfg.peft_use_dora
         LOG.info("Initializing LoRA weights using dora. This might take longer.")

src/axolotl/utils/samplers/utils.py

@@ -4,13 +4,17 @@ helper util to calculate dataset lengths
 import numpy as np
 
 
-def get_dataset_lengths(dataset):
+def get_dataset_lengths(dataset, from_arrow=False):
     if "length" in dataset.column_names:
         lengths = np.array(dataset["length"])
     elif "position_ids" in dataset.column_names:
         position_ids = dataset["position_ids"]
         lengths = np.array([x[-1] + 1 for x in position_ids])
     else:
-        input_ids = dataset["input_ids"]
-        lengths = np.array([len(seq) for seq in input_ids])
+        if from_arrow:
+            input_ids = dataset.data.column("input_ids")
+            lengths = np.vectorize(len)(np.array(input_ids, dtype=object))
+        else:
+            input_ids = dataset["input_ids"]
+            lengths = np.array([len(seq) for seq in input_ids])
     return lengths