ai-content-maker/.venv/Lib/site-packages/transformers/quantizers/quantizer_bnb_4bit.py

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2024-05-03 04:18:51 +03:00
# Copyright 2024 The HuggingFace Inc. team. All rights reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
import importlib
from typing import TYPE_CHECKING, Any, Dict, List, Optional, Union
from packaging import version
from .base import HfQuantizer
from .quantizers_utils import get_module_from_name
if TYPE_CHECKING:
from ..modeling_utils import PreTrainedModel
from ..utils import is_accelerate_available, is_bitsandbytes_available, is_torch_available, logging
if is_torch_available():
import torch
from ..pytorch_utils import Conv1D
logger = logging.get_logger(__name__)
class Bnb4BitHfQuantizer(HfQuantizer):
"""
4-bit quantization from bitsandbytes.py quantization method:
before loading: converts transformer layers into Linear4bit during loading: load 16bit weight and pass to the
layer object after: quantizes individual weights in Linear4bit into 4bit at the first .cuda() call
saving:
from state dict, as usual; saves weights and `quant_state` components
loading:
need to locate `quant_state` components and pass to Param4bit constructor
"""
use_keep_in_fp32_modules = True
requires_parameters_quantization = True
requires_calibration = False
required_packages = ["bitsandbytes", "accelerate"]
def __init__(self, quantization_config, **kwargs):
super().__init__(quantization_config, **kwargs)
if self.quantization_config.llm_int8_skip_modules is not None:
self.modules_to_not_convert = self.quantization_config.llm_int8_skip_modules
def validate_environment(self, *args, **kwargs):
if not (is_accelerate_available() and is_bitsandbytes_available()):
raise ImportError(
"Using `bitsandbytes` 8-bit quantization requires Accelerate: `pip install accelerate` "
"and the latest version of bitsandbytes: `pip install -i https://pypi.org/simple/ bitsandbytes`"
)
if kwargs.get("from_tf", False) or kwargs.get("from_flax", False):
raise ValueError(
"Converting into 4-bit or 8-bit weights from tf/flax weights is currently not supported, please make"
" sure the weights are in PyTorch format."
)
if not torch.cuda.is_available():
raise RuntimeError("No GPU found. A GPU is needed for quantization.")
device_map = kwargs.get("device_map", None)
if (
device_map is not None
and isinstance(device_map, dict)
and not self.quantization_config.llm_int8_enable_fp32_cpu_offload
):
device_map_without_lm_head = {
key: device_map[key] for key in device_map.keys() if key not in self.modules_to_not_convert
}
if "cpu" in device_map_without_lm_head.values() or "disk" in device_map_without_lm_head.values():
raise ValueError(
"""
Some modules are dispatched on the CPU or the disk. Make sure you have enough GPU RAM to fit the
quantized model. If you want to dispatch the model on the CPU or the disk while keeping these modules
in 32-bit, you need to set `llm_int8_enable_fp32_cpu_offload=True` and pass a custom `device_map` to
`from_pretrained`. Check
https://huggingface.co/docs/transformers/main/en/main_classes/quantization#offload-between-cpu-and-gpu
for more details.
"""
)
if version.parse(importlib.metadata.version("bitsandbytes")) < version.parse("0.39.0"):
raise ValueError(
"You have a version of `bitsandbytes` that is not compatible with 4bit inference and training"
" make sure you have the latest version of `bitsandbytes` installed"
)
def adjust_target_dtype(self, target_dtype: "torch.dtype") -> "torch.dtype":
if version.parse(importlib.metadata.version("accelerate")) > version.parse("0.19.0"):
from accelerate.utils import CustomDtype
if target_dtype != torch.int8:
logger.info("target_dtype {target_dtype} is replaced by `CustomDtype.INT4` for 4-bit BnB quantization")
return CustomDtype.INT4
else:
raise ValueError(
"You are using `device_map='auto'` on a 4bit loaded version of the model. To automatically compute"
" the appropriate device map, you should upgrade your `accelerate` library,"
"`pip install --upgrade accelerate` or install it from source to support fp4 auto device map"
"calculation. You may encounter unexpected behavior, or pass your own device map"
)
def check_quantized_param(
self,
model: "PreTrainedModel",
param_value: "torch.Tensor",
param_name: str,
state_dict: Dict[str, Any],
**kwargs,
) -> bool:
import bitsandbytes as bnb
module, tensor_name = get_module_from_name(model, param_name)
if isinstance(module._parameters.get(tensor_name, None), bnb.nn.Params4bit):
# Add here check for loaded components' dtypes once serialization is implemented
return True
elif isinstance(module, bnb.nn.Linear4bit) and tensor_name == "bias":
# bias could be loaded by regular set_module_tensor_to_device() from accelerate,
# but it would wrongly use uninitialized weight there.
return True
else:
return False
def create_quantized_param(
self,
model: "PreTrainedModel",
param_value: "torch.Tensor",
param_name: str,
target_device: "torch.device",
state_dict: Dict[str, Any],
unexpected_keys: Optional[List[str]] = None,
):
"""
combines logic from _load_state_dict_into_meta_model and .integrations.bitsandbytes.py::set_module_quantized_tensor_to_device()
"""
import bitsandbytes as bnb
module, tensor_name = get_module_from_name(model, param_name)
if tensor_name not in module._parameters:
raise ValueError(f"{module} does not have a parameter or a buffer named {tensor_name}.")
old_value = getattr(module, tensor_name)
if tensor_name == "bias":
if param_value is None:
new_value = old_value.to(target_device)
else:
new_value = param_value.to(target_device)
new_value = torch.nn.Parameter(new_value, requires_grad=old_value.requires_grad)
module._parameters[tensor_name] = new_value
return
if not isinstance(module._parameters[tensor_name], bnb.nn.Params4bit):
raise ValueError("this function only loads `Linear4bit components`")
if (
old_value.device == torch.device("meta")
and target_device not in ["meta", torch.device("meta")]
and param_value is None
):
raise ValueError(f"{tensor_name} is on the meta device, we need a `value` to put in on {target_device}.")
# construct `new_value` for the module._parameters[tensor_name]:
if self.pre_quantized:
# 4bit loading. Collecting components for restoring quantized weight
# This can be expanded to make a universal call for any quantized weight loading
if not self.is_serializable:
raise ValueError(
"Detected int4 weights but the version of bitsandbytes is not compatible with int4 serialization. "
"Make sure to download the latest `bitsandbytes` version. `pip install --upgrade bitsandbytes`."
)
if (param_name + ".quant_state.bitsandbytes__fp4" not in state_dict) and (
param_name + ".quant_state.bitsandbytes__nf4" not in state_dict
):
raise ValueError(
f"Supplied state dict for {param_name} does not contain `bitsandbytes__*` and possibly other `quantized_stats` components."
)
quantized_stats = {}
for k, v in state_dict.items():
if param_name + "." in k:
quantized_stats[k] = v
if unexpected_keys is not None and k in unexpected_keys:
unexpected_keys.remove(k)
new_value = bnb.nn.Params4bit.from_prequantized(
data=param_value,
quantized_stats=quantized_stats,
requires_grad=False,
device=target_device,
)
else:
new_value = param_value.to("cpu")
# Support models using `Conv1D` in place of `nn.Linear` (e.g. openai-community/gpt2) by transposing the weight matrix prior to quantization.
# Since weights are saved in the correct "orientation", we skip transposing when loading.
if issubclass(module.source_cls, Conv1D):
new_value = new_value.T
kwargs = old_value.__dict__
new_value = bnb.nn.Params4bit(new_value, requires_grad=False, **kwargs).to(target_device)
module._parameters[tensor_name] = new_value
# Copied from transformers.quantizers.quantizer_bnb_8bit.Bnb8BitHfQuantizer.adjust_max_memory
def adjust_max_memory(self, max_memory: Dict[str, Union[int, str]]) -> Dict[str, Union[int, str]]:
# need more space for buffers that are created during quantization
max_memory = {key: val * 0.90 for key, val in max_memory.items()}
return max_memory
# Copied from transformers.quantizers.quantizer_bnb_8bit.Bnb8BitHfQuantizer.update_torch_dtype
def update_torch_dtype(self, torch_dtype: "torch.dtype") -> "torch.dtype":
if torch_dtype is None:
# We force the `dtype` to be float16, this is a requirement from `bitsandbytes`
logger.info(
"Overriding torch_dtype=%s with `torch_dtype=torch.float16` due to "
"requirements of `bitsandbytes` to enable model loading in 8-bit or 4-bit. "
"Pass your own torch_dtype to specify the dtype of the remaining non-linear layers or pass"
" torch_dtype=torch.float16 to remove this warning.",
torch_dtype,
)
torch_dtype = torch.float16
return torch_dtype
# Copied from transformers.quantizers.quantizer_bnb_8bit.Bnb8BitHfQuantizer.update_device_map
def update_device_map(self, device_map):
if device_map is None:
device_map = {"": torch.cuda.current_device()}
logger.info(
"The device_map was not initialized. "
"Setting device_map to {'':torch.cuda.current_device()}. "
"If you want to use the model for inference, please set device_map ='auto' "
)
return device_map
# Copied from transformers.quantizers.quantizer_bnb_8bit.Bnb8BitHfQuantizer._process_model_before_weight_loading
def _process_model_before_weight_loading(
self,
model: "PreTrainedModel",
device_map,
keep_in_fp32_modules: List[str] = [],
**kwargs,
):
from ..integrations import get_keys_to_not_convert, replace_with_bnb_linear
load_in_8bit_fp32_cpu_offload = self.quantization_config.llm_int8_enable_fp32_cpu_offload
# We keep some modules such as the lm_head in their original dtype for numerical stability reasons
if self.quantization_config.llm_int8_skip_modules is None:
self.modules_to_not_convert = get_keys_to_not_convert(model)
else:
self.modules_to_not_convert = self.quantization_config.llm_int8_skip_modules
if not isinstance(self.modules_to_not_convert, list):
self.modules_to_not_convert = [self.modules_to_not_convert]
self.modules_to_not_convert.extend(keep_in_fp32_modules)
# Extend `self.modules_to_not_convert` to keys that are supposed to be offloaded to `cpu` or `disk`
if isinstance(device_map, dict) and len(device_map.keys()) > 1:
keys_on_cpu = [key for key, value in device_map.items() if value in ["disk", "cpu"]]
if len(keys_on_cpu) > 0 and not load_in_8bit_fp32_cpu_offload:
raise ValueError(
"If you want to offload some keys to `cpu` or `disk`, you need to set "
"`llm_int8_enable_fp32_cpu_offload=True`. Note that these modules will not be "
" converted to 8-bit but kept in 32-bit."
)
self.modules_to_not_convert.extend(keys_on_cpu)
model = replace_with_bnb_linear(
model, modules_to_not_convert=self.modules_to_not_convert, quantization_config=self.quantization_config
)
# TODO: consider bringing replace_with_bnb_linear() code from ..integrations/bitsandbyter.py to here
model.config.quantization_config = self.quantization_config
# Copied from transformers.quantizers.quantizer_bnb_8bit.Bnb8BitHfQuantizer._process_model_after_weight_loading with 8bit->4bit
def _process_model_after_weight_loading(self, model: "PreTrainedModel", **kwargs):
model.is_loaded_in_4bit = True
model.is_4bit_serializable = self.is_serializable
return model
@property
def is_serializable(self):
_is_4bit_serializable = version.parse(importlib.metadata.version("bitsandbytes")) >= version.parse("0.41.3")
if not _is_4bit_serializable:
logger.warning(
"You are calling `save_pretrained` to a 4-bit converted model, but your `bitsandbytes` version doesn't support it. "
"If you want to save 4-bit models, make sure to have `bitsandbytes>=0.41.3` installed."
)
return False
return True
@property
def is_trainable(self) -> bool:
return True