lora+ support (#1352)

* lora+ support

* optimizer should default to None

* include mit license

src/axolotl/core/trainer_builder.py

@@ -27,8 +27,10 @@ from transformers import (
     TrainingArguments,
 )
 from transformers.trainer_utils import seed_worker
+from transformers.utils import is_sagemaker_mp_enabled
 from trl import DPOTrainer
 
+from axolotl.loraplus import create_loraplus_optimizer
 from axolotl.monkeypatch.multipack import SUPPORTED_MULTIPACK_MODEL_TYPES
 from axolotl.monkeypatch.relora import ReLoRACallback, ReLoRAScheduler
 from axolotl.utils.callbacks import (
@@ -54,6 +56,9 @@ from axolotl.utils.schedulers import (
     get_cosine_schedule_with_warmup_decay_constant,
 )
 
+if is_sagemaker_mp_enabled():
+    import smdistributed.modelparallel.torch as smp
+
 try:
     import torch._dynamo  # pylint: disable=ungrouped-imports
 except ImportError:
@@ -179,6 +184,13 @@ class AxolotlTrainingArguments(TrainingArguments):
             "help": "Starting constant learning rate step is cosine_constant_lr_ratio * max_steps"
         },
     )
+    loraplus_lr_ratio: Optional[float] = field(
+        default=None, metadata={"help": "loraplus learning rate ratio lr_B / lr_A."}
+    )
+    loraplus_lr_embedding: Optional[float] = field(
+        default=1e-6,
+        metadata={"help": "loraplus learning rate for lora embedding layers."},
+    )
 
 
 class AxolotlTrainer(Trainer):
@@ -203,6 +215,33 @@ class AxolotlTrainer(Trainer):
         super().__init__(*_args, **kwargs)
         self.train_data_collator = self.data_collator
 
+    def create_optimizer(self):
+        if self.args.loraplus_lr_ratio is None:
+            return super().create_optimizer()
+
+        opt_model = self.model_wrapped if is_sagemaker_mp_enabled() else self.model
+        if self.optimizer is None:  # pylint: disable=access-member-before-definition
+            optimizer_cls, optimizer_kwargs = Trainer.get_optimizer_cls_and_kwargs(
+                self.args,
+            )
+
+            loraplus_lr_ratio = getattr(self.args, "loraplus_lr_ratio", None)
+            loraplus_lr_embedding = getattr(self.args, "loraplus_lr_embedding", None)
+            self.optimizer = create_loraplus_optimizer(  # pylint: disable=attribute-defined-outside-init
+                opt_model,
+                optimizer_cls,
+                optimizer_kwargs,
+                loraplus_lr_ratio,
+                loraplus_lr_embedding,
+            )
+
+        if is_sagemaker_mp_enabled():
+            self.optimizer = smp.DistributedOptimizer(  # pylint: disable=attribute-defined-outside-init
+                self.optimizer
+            )
+
+        return self.optimizer
+
     def create_scheduler(
         self, num_training_steps: int, optimizer: torch.optim.Optimizer = None
     ):
@@ -915,6 +954,10 @@ class HFCausalTrainerBuilder(TrainerBuilderBase):
         training_arguments_kwargs["optim"] = (
             self.cfg.optimizer if self.cfg.optimizer else "adamw_hf"
         )
+        training_arguments_kwargs["loraplus_lr_ratio"] = self.cfg.loraplus_lr_ratio
+        training_arguments_kwargs[
+            "loraplus_lr_embedding"
+        ] = self.cfg.loraplus_lr_embedding
         training_arguments_kwargs["lr_scheduler_type"] = (
             self.cfg.lr_scheduler
             if self.cfg.lr_scheduler

src/axolotl/loraplus.py

@@ -0,0 +1,133 @@
+"""Module for LoRA+"""
+
+# MIT License
+#
+# Copyright (c) 2024 nikhil-ghosh-berkeley
+# https://github.com/nikhil-ghosh-berkeley/loraplus
+
+import logging
+from functools import reduce
+
+from peft.tuners import lora
+from torch import nn
+from transformers.pytorch_utils import ALL_LAYERNORM_LAYERS
+from transformers.trainer_pt_utils import get_parameter_names
+
+LOG = logging.getLogger("axolotl.loraplus")
+
+
+def get_module(name, opt_model):
+    """
+    Retrieve a module from a model using its parameter name.
+    Args:
+        name (str): Full name of the parameter, typically including module path.
+        opt_model (torch.nn.Module): The model from which to retrieve the module.
+
+    Returns:
+        Module corresponding to the given name.
+    """
+    parent_idx = 2 if "lora" in name else 1
+    module_names = name.split(sep=".")[:-parent_idx]
+    module = reduce(getattr, module_names, opt_model)
+    return module
+
+
+def create_loraplus_optimizer(
+    opt_model,
+    optimizer_cls,
+    optimizer_kwargs,
+    loraplus_lr_ratio,
+    loraplus_lr_embedding=None,
+):
+    """
+    Creates an optimizer for the given model, applying LoRA-specific learning rate adjustments to different parameter groups.
+
+    Args:
+        opt_model (torch.nn.Module): The model for which the optimizer is being created.
+        optimizer_cls (class): The class of the optimizer to be used (e.g., torch.optim.Adam).
+        optimizer_kwargs (dict): A dictionary of keyword arguments for the optimizer's initialization.
+        loraplus_lr_ratio (float): The learning rate ratio to be applied to LoRA parameters.
+        loraplus_lr_embedding (float, optional): A specific learning rate for embedding parameters, with a default value if not provided.
+
+    Returns:
+        An instance of the specified optimizer class configured with the model's parameters organized into groups with custom learning rates.
+    """
+
+    assert loraplus_lr_ratio is not None, "loraplus_lr_ratio must be provided."
+
+    if loraplus_lr_embedding is None:
+        loraplus_lr_embedding = 1e-6
+
+    decay_parameters = get_parameter_names(opt_model, ALL_LAYERNORM_LAYERS)
+    decay_parameters = [name for name in decay_parameters if "bias" not in name]
+    param_groups = {
+        "groupA": {},
+        "groupB": {},
+        "groupB_no_decay": {},
+        "embedding": {},
+    }
+
+    for name, param in opt_model.named_parameters():
+        if not param.requires_grad:
+            continue
+
+        module = get_module(name, opt_model)
+        if isinstance(module, lora.Embedding):
+            param_groups["embedding"][name] = param
+        elif "lora_B" in name or param.ndim == 1:
+            if name in decay_parameters:
+                param_groups["groupB"][name] = param
+            else:
+                param_groups["groupB_no_decay"][name] = param
+        else:
+            param_groups["groupA"][name] = param
+
+    assigned_param_groups = ""
+    for group, group_params in param_groups.items():
+        assigned_param_groups += f"{group}\n {list(group_params.keys())}\n\n"
+    LOG.info(assigned_param_groups)
+
+    lr = optimizer_kwargs["lr"]  # pylint: disable=invalid-name
+    weight_decay = optimizer_kwargs.get("weight_decay", 0.0)
+
+    optimizer_grouped_parameters = [
+        {
+            "params": list(param_groups["groupA"].values()),
+            "weight_decay": weight_decay,
+            "lr": lr,
+        },
+        {
+            "params": list(param_groups["embedding"].values()),
+            "weight_decay": weight_decay,
+            "lr": loraplus_lr_embedding,
+        },
+        {
+            "params": list(param_groups["groupB"].values()),
+            "weight_decay": weight_decay,
+            "lr": lr * loraplus_lr_ratio,
+        },
+        {
+            "params": list(param_groups["groupB_no_decay"].values()),
+            "weight_decay": 0.0,
+            "lr": lr * loraplus_lr_ratio,
+        },
+    ]
+
+    optimizer = optimizer_cls(optimizer_grouped_parameters, **optimizer_kwargs)
+    if optimizer_cls.__name__ == "Adam8bit":
+        import bitsandbytes
+
+        manager = bitsandbytes.optim.GlobalOptimManager.get_instance()
+
+        skipped = 0
+        for module in opt_model.modules():
+            if isinstance(module, nn.Embedding):
+                skipped += sum(
+                    {p.data_ptr(): p.numel() for p in module.parameters()}.values()
+                )
+                LOG.info(f"skipped {module}: {skipped/2**20}M params")
+                manager.register_module_override(module, "weight", {"optim_bits": 32})
+                LOG.debug(f"bitsandbytes: will optimize {module} in fp32")
+        LOG.info(f"skipped: {skipped/2**20}M params")
+
+    return optimizer

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

@@ -183,6 +183,17 @@ class LoraConfig(BaseModel):
     gptq: Optional[bool] = None
     bnb_config_kwargs: Optional[Dict[str, Any]] = None
 
+    loraplus_lr_ratio: Optional[float] = Field(
+        default=None,
+        metadata={
+            "help": "loraplus learning rate ratio lr_B / lr_A. Recommended value is 2^4."
+        },
+    )
+    loraplus_lr_embedding: Optional[float] = Field(
+        default=1e-6,
+        metadata={"help": "loraplus learning rate for lora embedding layers."},
+    )
+
     merge_lora: Optional[bool] = None
 
     @model_validator(mode="before")