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#!/usr/bin/env python
# coding=utf-8
# Copyright 2023 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.
"""
Adapted from
https://github.com/huggingface/transformers/blob/52cb4034ada381fe1ffe8d428a1076e5411a8026/src/transformers/utils/quantization_config.py
"""
from __future__ import annotations
import copy
import importlib.metadata
import json
import os
import warnings
from dataclasses import dataclass
from enum import Enum
from typing import Any, Callable
from packaging import version
from ..utils import deprecate, is_torch_available, is_torchao_version, logging
if is_torch_available():
import torch
logger = logging.get_logger(__name__)
class QuantizationMethod(str, Enum):
BITS_AND_BYTES = "bitsandbytes"
GGUF = "gguf"
TORCHAO = "torchao"
QUANTO = "quanto"
MODELOPT = "modelopt"
@dataclass
class QuantizationConfigMixin:
"""
Mixin class for quantization config
"""
quant_method: QuantizationMethod
_exclude_attributes_at_init = []
@classmethod
def from_dict(cls, config_dict, return_unused_kwargs=False, **kwargs):
"""
Instantiates a [`QuantizationConfigMixin`] from a Python dictionary of parameters.
Args:
config_dict (`dict[str, Any]`):
Dictionary that will be used to instantiate the configuration object.
return_unused_kwargs (`bool`, *optional*, defaults to `False`):
Whether or not to return a list of unused keyword arguments. Used for `from_pretrained` method in
`PreTrainedModel`.
kwargs (`dict[str, Any]`):
Additional parameters from which to initialize the configuration object.
Returns:
[`QuantizationConfigMixin`]: The configuration object instantiated from those parameters.
"""
config = cls(**config_dict)
to_remove = []
for key, value in kwargs.items():
if hasattr(config, key):
setattr(config, key, value)
to_remove.append(key)
for key in to_remove:
kwargs.pop(key, None)
if return_unused_kwargs:
return config, kwargs
else:
return config
def to_json_file(self, json_file_path: str | os.PathLike):
"""
Save this instance to a JSON file.
Args:
json_file_path (`str` or `os.PathLike`):
Path to the JSON file in which this configuration instance's parameters will be saved.
use_diff (`bool`, *optional*, defaults to `True`):
If set to `True`, only the difference between the config instance and the default
`QuantizationConfig()` is serialized to JSON file.
"""
with open(json_file_path, "w", encoding="utf-8") as writer:
config_dict = self.to_dict()
json_string = json.dumps(config_dict, indent=2, sort_keys=True) + "\n"
writer.write(json_string)
def to_dict(self) -> dict[str, Any]:
"""
Serializes this instance to a Python dictionary. Returns:
`dict[str, Any]`: Dictionary of all the attributes that make up this configuration instance.
"""
return copy.deepcopy(self.__dict__)
def __iter__(self):
"""allows `dict(obj)` for situations where obj may be a dict or QuantizationConfigMixin"""
for attr, value in copy.deepcopy(self.__dict__).items():
yield attr, value
def __repr__(self):
return f"{self.__class__.__name__} {self.to_json_string()}"
def to_json_string(self, use_diff: bool = True) -> str:
"""
Serializes this instance to a JSON string.
Args:
use_diff (`bool`, *optional*, defaults to `True`):
If set to `True`, only the difference between the config instance and the default `PretrainedConfig()`
is serialized to JSON string.
Returns:
`str`: String containing all the attributes that make up this configuration instance in JSON format.
"""
if use_diff is True:
config_dict = self.to_diff_dict()
else:
config_dict = self.to_dict()
return json.dumps(config_dict, indent=2, sort_keys=True) + "\n"
def update(self, **kwargs):
"""
Updates attributes of this class instance with attributes from `kwargs` if they match existing attributes,
returning all the unused kwargs.
Args:
kwargs (`dict[str, Any]`):
Dictionary of attributes to tentatively update this class.
Returns:
`dict[str, Any]`: Dictionary containing all the key-value pairs that were not used to update the instance.
"""
to_remove = []
for key, value in kwargs.items():
if hasattr(self, key):
setattr(self, key, value)
to_remove.append(key)
# Remove all the attributes that were updated, without modifying the input dict
unused_kwargs = {key: value for key, value in kwargs.items() if key not in to_remove}
return unused_kwargs
@dataclass
class BitsAndBytesConfig(QuantizationConfigMixin):
"""
This is a wrapper class about all possible attributes and features that you can play with a model that has been
loaded using `bitsandbytes`.
This replaces `load_in_8bit` or `load_in_4bit` therefore both options are mutually exclusive.
Currently only supports `LLM.int8()`, `FP4`, and `NF4` quantization. If more methods are added to `bitsandbytes`,
then more arguments will be added to this class.
Args:
load_in_8bit (`bool`, *optional*, defaults to `False`):
This flag is used to enable 8-bit quantization with LLM.int8().
load_in_4bit (`bool`, *optional*, defaults to `False`):
This flag is used to enable 4-bit quantization by replacing the Linear layers with FP4/NF4 layers from
`bitsandbytes`.
llm_int8_threshold (`float`, *optional*, defaults to 6.0):
This corresponds to the outlier threshold for outlier detection as described in `LLM.int8() : 8-bit Matrix
Multiplication for Transformers at Scale` paper: https://huggingface.co/papers/2208.07339 Any hidden states
value that is above this threshold will be considered an outlier and the operation on those values will be
done in fp16. Values are usually normally distributed, that is, most values are in the range [-3.5, 3.5],
but there are some exceptional systematic outliers that are very differently distributed for large models.
These outliers are often in the interval [-60, -6] or [6, 60]. Int8 quantization works well for values of
magnitude ~5, but beyond that, there is a significant performance penalty. A good default threshold is 6,
but a lower threshold might be needed for more unstable models (small models, fine-tuning).
llm_int8_skip_modules (`list[str]`, *optional*):
An explicit list of the modules that we do not want to convert in 8-bit. This is useful for models such as
Jukebox that has several heads in different places and not necessarily at the last position. For example
for `CausalLM` models, the last `lm_head` is typically kept in its original `dtype`.
llm_int8_enable_fp32_cpu_offload (`bool`, *optional*, defaults to `False`):
This flag is used for advanced use cases and users that are aware of this feature. If you want to split
your model in different parts and run some parts in int8 on GPU and some parts in fp32 on CPU, you can use
this flag. This is useful for offloading large models such as `google/flan-t5-xxl`. Note that the int8
operations will not be run on CPU.
llm_int8_has_fp16_weight (`bool`, *optional*, defaults to `False`):
This flag runs LLM.int8() with 16-bit main weights. This is useful for fine-tuning as the weights do not
have to be converted back and forth for the backward pass.
bnb_4bit_compute_dtype (`torch.dtype` or str, *optional*, defaults to `torch.float32`):
This sets the computational type which might be different than the input type. For example, inputs might be
fp32, but computation can be set to bf16 for speedups.
bnb_4bit_quant_type (`str`, *optional*, defaults to `"fp4"`):
This sets the quantization data type in the bnb.nn.Linear4Bit layers. Options are FP4 and NF4 data types
which are specified by `fp4` or `nf4`.
bnb_4bit_use_double_quant (`bool`, *optional*, defaults to `False`):
This flag is used for nested quantization where the quantization constants from the first quantization are
quantized again.
bnb_4bit_quant_storage (`torch.dtype` or str, *optional*, defaults to `torch.uint8`):
This sets the storage type to pack the quanitzed 4-bit prarams.
kwargs (`dict[str, Any]`, *optional*):
Additional parameters from which to initialize the configuration object.
"""
_exclude_attributes_at_init = ["_load_in_4bit", "_load_in_8bit", "quant_method"]
def __init__(
self,
load_in_8bit=False,
load_in_4bit=False,
llm_int8_threshold=6.0,
llm_int8_skip_modules=None,
llm_int8_enable_fp32_cpu_offload=False,
llm_int8_has_fp16_weight=False,
bnb_4bit_compute_dtype=None,
bnb_4bit_quant_type="fp4",
bnb_4bit_use_double_quant=False,
bnb_4bit_quant_storage=None,
**kwargs,
):
self.quant_method = QuantizationMethod.BITS_AND_BYTES
if load_in_4bit and load_in_8bit:
raise ValueError("load_in_4bit and load_in_8bit are both True, but only one can be used at the same time")
self._load_in_8bit = load_in_8bit
self._load_in_4bit = load_in_4bit
self.llm_int8_threshold = llm_int8_threshold
self.llm_int8_skip_modules = llm_int8_skip_modules
self.llm_int8_enable_fp32_cpu_offload = llm_int8_enable_fp32_cpu_offload
self.llm_int8_has_fp16_weight = llm_int8_has_fp16_weight
self.bnb_4bit_quant_type = bnb_4bit_quant_type
self.bnb_4bit_use_double_quant = bnb_4bit_use_double_quant
if bnb_4bit_compute_dtype is None:
self.bnb_4bit_compute_dtype = torch.float32
elif isinstance(bnb_4bit_compute_dtype, str):
self.bnb_4bit_compute_dtype = getattr(torch, bnb_4bit_compute_dtype)
elif isinstance(bnb_4bit_compute_dtype, torch.dtype):
self.bnb_4bit_compute_dtype = bnb_4bit_compute_dtype
else:
raise ValueError("bnb_4bit_compute_dtype must be a string or a torch.dtype")
if bnb_4bit_quant_storage is None:
self.bnb_4bit_quant_storage = torch.uint8
elif isinstance(bnb_4bit_quant_storage, str):
if bnb_4bit_quant_storage not in [
"float16",
"float32",
"int8",
"uint8",
"float64",
"bfloat16",
]:
raise ValueError(
"`bnb_4bit_quant_storage` must be a valid string (one of 'float16', 'float32', 'int8', 'uint8', 'float64', 'bfloat16') "
)
self.bnb_4bit_quant_storage = getattr(torch, bnb_4bit_quant_storage)
elif isinstance(bnb_4bit_quant_storage, torch.dtype):
self.bnb_4bit_quant_storage = bnb_4bit_quant_storage
else:
raise ValueError("bnb_4bit_quant_storage must be a string or a torch.dtype")
if kwargs and not all(k in self._exclude_attributes_at_init for k in kwargs):
logger.warning(f"Unused kwargs: {list(kwargs.keys())}. These kwargs are not used in {self.__class__}.")
self.post_init()
@property
def load_in_4bit(self):
return self._load_in_4bit
@load_in_4bit.setter
def load_in_4bit(self, value: bool):
if not isinstance(value, bool):
raise TypeError("load_in_4bit must be a boolean")
if self.load_in_8bit and value:
raise ValueError("load_in_4bit and load_in_8bit are both True, but only one can be used at the same time")
self._load_in_4bit = value
@property
def load_in_8bit(self):
return self._load_in_8bit
@load_in_8bit.setter
def load_in_8bit(self, value: bool):
if not isinstance(value, bool):
raise TypeError("load_in_8bit must be a boolean")
if self.load_in_4bit and value:
raise ValueError("load_in_4bit and load_in_8bit are both True, but only one can be used at the same time")
self._load_in_8bit = value
def post_init(self):
r"""
Safety checker that arguments are correct - also replaces some NoneType arguments with their default values.
"""
if not isinstance(self.load_in_4bit, bool):
raise TypeError("load_in_4bit must be a boolean")
if not isinstance(self.load_in_8bit, bool):
raise TypeError("load_in_8bit must be a boolean")
if not isinstance(self.llm_int8_threshold, float):
raise TypeError("llm_int8_threshold must be a float")
if self.llm_int8_skip_modules is not None and not isinstance(self.llm_int8_skip_modules, list):
raise TypeError("llm_int8_skip_modules must be a list of strings")
if not isinstance(self.llm_int8_enable_fp32_cpu_offload, bool):
raise TypeError("llm_int8_enable_fp32_cpu_offload must be a boolean")
if not isinstance(self.llm_int8_has_fp16_weight, bool):
raise TypeError("llm_int8_has_fp16_weight must be a boolean")
if self.bnb_4bit_compute_dtype is not None and not isinstance(self.bnb_4bit_compute_dtype, torch.dtype):
raise TypeError("bnb_4bit_compute_dtype must be torch.dtype")
if not isinstance(self.bnb_4bit_quant_type, str):
raise TypeError("bnb_4bit_quant_type must be a string")
if not isinstance(self.bnb_4bit_use_double_quant, bool):
raise TypeError("bnb_4bit_use_double_quant must be a boolean")
if self.load_in_4bit and not version.parse(importlib.metadata.version("bitsandbytes")) >= version.parse(
"0.39.0"
):
raise ValueError(
"4 bit quantization requires bitsandbytes>=0.39.0 - please upgrade your bitsandbytes version"
)
def is_quantizable(self):
r"""
Returns `True` if the model is quantizable, `False` otherwise.
"""
return self.load_in_8bit or self.load_in_4bit
def quantization_method(self):
r"""
This method returns the quantization method used for the model. If the model is not quantizable, it returns
`None`.
"""
if self.load_in_8bit:
return "llm_int8"
elif self.load_in_4bit and self.bnb_4bit_quant_type == "fp4":
return "fp4"
elif self.load_in_4bit and self.bnb_4bit_quant_type == "nf4":
return "nf4"
else:
return None
def to_dict(self) -> dict[str, Any]:
"""
Serializes this instance to a Python dictionary. Returns:
`dict[str, Any]`: Dictionary of all the attributes that make up this configuration instance.
"""
output = copy.deepcopy(self.__dict__)
output["bnb_4bit_compute_dtype"] = str(output["bnb_4bit_compute_dtype"]).split(".")[1]
output["bnb_4bit_quant_storage"] = str(output["bnb_4bit_quant_storage"]).split(".")[1]
output["load_in_4bit"] = self.load_in_4bit
output["load_in_8bit"] = self.load_in_8bit
return output
def __repr__(self):
config_dict = self.to_dict()
return f"{self.__class__.__name__} {json.dumps(config_dict, indent=2, sort_keys=True)}\n"
def to_diff_dict(self) -> dict[str, Any]:
"""
Removes all attributes from config which correspond to the default config attributes for better readability and
serializes to a Python dictionary.
Returns:
`dict[str, Any]`: Dictionary of all the attributes that make up this configuration instance,
"""
config_dict = self.to_dict()
# get the default config dict
default_config_dict = BitsAndBytesConfig().to_dict()
serializable_config_dict = {}
# only serialize values that differ from the default config
for key, value in config_dict.items():
if value != default_config_dict[key]:
serializable_config_dict[key] = value
return serializable_config_dict
@dataclass
class GGUFQuantizationConfig(QuantizationConfigMixin):
"""This is a config class for GGUF Quantization techniques.
Args:
compute_dtype: (`torch.dtype`, defaults to `torch.float32`):
This sets the computational type which might be different than the input type. For example, inputs might be
fp32, but computation can be set to bf16 for speedups.
"""
def __init__(self, compute_dtype: "torch.dtype" | None = None):
self.quant_method = QuantizationMethod.GGUF
self.compute_dtype = compute_dtype
self.pre_quantized = True
# TODO: (Dhruv) Add this as an init argument when we can support loading unquantized checkpoints.
self.modules_to_not_convert = None
if self.compute_dtype is None:
self.compute_dtype = torch.float32
@dataclass
class TorchAoConfig(QuantizationConfigMixin):
"""This is a config class for torchao quantization/sparsity techniques.
Args:
quant_type (`AOBaseConfig`):
An `AOBaseConfig` subclass instance specifying the quantization type. See the [torchao
documentation](https://docs.pytorch.org/ao/main/api_ref_quantization.html#inference-apis-for-quantize) for
available config classes (e.g. `Int4WeightOnlyConfig`, `Int8WeightOnlyConfig`, `Float8WeightOnlyConfig`,
`Float8DynamicActivationFloat8WeightConfig`, etc.).
modules_to_not_convert (`list[str]`, *optional*, default to `None`):
The list of modules to not quantize, useful for quantizing models that explicitly require to have some
modules left in their original precision.
Example:
```python
from diffusers import FluxTransformer2DModel, TorchAoConfig
from torchao.quantization import Int8WeightOnlyConfig
quantization_config = TorchAoConfig(Int8WeightOnlyConfig())
transformer = FluxTransformer2DModel.from_pretrained(
"black-forest-labs/Flux.1-Dev",
subfolder="transformer",
quantization_config=quantization_config,
torch_dtype=torch.bfloat16,
)
```
"""
def __init__(
self,
quant_type: "AOBaseConfig", # noqa: F821
modules_to_not_convert: list[str] | None = None,
**kwargs,
) -> None:
self.quant_method = QuantizationMethod.TORCHAO
self.quant_type = quant_type
self.modules_to_not_convert = modules_to_not_convert
self.post_init()
def post_init(self):
if is_torchao_version("<", "0.15.0"):
raise ValueError("TorchAoConfig requires torchao >= 0.15.0. Please upgrade with `pip install -U torchao`.")
from torchao.quantization.quant_api import AOBaseConfig
if not isinstance(self.quant_type, AOBaseConfig):
raise TypeError(f"quant_type must be an AOBaseConfig instance, got {type(self.quant_type).__name__}")
def to_dict(self):
"""Convert configuration to a dictionary."""
d = super().to_dict()
# Handle AOBaseConfig serialization
from torchao.core.config import config_to_dict
# For now we assume there is 1 config per Transformer, however in the future
# we may want to support a config per fqn.
# See: https://docs.pytorch.org/ao/stable/api_reference/generated/torchao.quantization.quantize_.html
d["quant_type"] = {"default": config_to_dict(self.quant_type)}
return d
@classmethod
def from_dict(cls, config_dict, return_unused_kwargs=False, **kwargs):
"""Create configuration from a dictionary."""
if not is_torchao_version(">=", "0.15.0"):
raise NotImplementedError("TorchAoConfig requires torchao >= 0.15.0 for construction from dict")
config_dict = config_dict.copy()
quant_type = config_dict.pop("quant_type")
# Check if we only have one key which is "default"
# In the future we may update this
assert len(quant_type) == 1 and "default" in quant_type, (
"Expected only one key 'default' in quant_type dictionary"
)
quant_type = quant_type["default"]
# Deserialize quant_type if needed
from torchao.core.config import config_from_dict
quant_type = config_from_dict(quant_type)
return cls(quant_type=quant_type, **config_dict)
def get_apply_tensor_subclass(self):
"""Create the appropriate quantization method based on configuration."""
return self.quant_type
def __repr__(self):
config_dict = self.to_dict()
return f"{self.__class__.__name__} {json.dumps(config_dict, indent=2, sort_keys=True)}\n"
@dataclass
class QuantoConfig(QuantizationConfigMixin):
"""
This is a wrapper class about all possible attributes and features that you can play with a model that has been
loaded using `quanto`.
Args:
weights_dtype (`str`, *optional*, defaults to `"int8"`):
The target dtype for the weights after quantization. Supported values are ("float8","int8","int4","int2")
modules_to_not_convert (`list`, *optional*, default to `None`):
The list of modules to not quantize, useful for quantizing models that explicitly require to have some
modules left in their original precision (e.g. Whisper encoder, Llava encoder, Mixtral gate layers).
"""
def __init__(
self,
weights_dtype: str = "int8",
modules_to_not_convert: list[str] | None = None,
**kwargs,
):
deprecation_message = "`QuantoConfig` is deprecated and will be removed in version 1.0.0."
deprecate("QuantoConfig", "1.0.0", deprecation_message)
self.quant_method = QuantizationMethod.QUANTO
self.weights_dtype = weights_dtype
self.modules_to_not_convert = modules_to_not_convert
self.post_init()
def post_init(self):
r"""
Safety checker that arguments are correct
"""
accepted_weights = ["float8", "int8", "int4", "int2"]
if self.weights_dtype not in accepted_weights:
raise ValueError(f"Only support weights in {accepted_weights} but found {self.weights_dtype}")
@dataclass
class NVIDIAModelOptConfig(QuantizationConfigMixin):
"""This is a config class to use nvidia modelopt for quantization.
Args:
quant_type (`str`):
The type of quantization we want to use, following is how to use:
**weightquant_activationquant ==> FP8_FP8** In the above example we have use FP8 for both weight and
activation quantization. Following are the all the options:
- FP8
- INT8
- INT4
- NF4
- NVFP4
modules_to_not_convert (`list[str]`, *optional*, default to `None`):
The list of modules to not quantize, useful for quantizing models that explicitly require to have some
weight_only (`bool`, *optional*, default to `False`):
If set to `True`, the quantization will be applied only to the weights of the model.
channel_quantize (`int`, *optional*, default to `None`):
The channel quantization axis, useful for quantizing models across different axes.
block_quantize (`int`, *optional*, default to `None`):
The block size, useful to further quantize each channel/axes into blocks.
scale_channel_quantize (`int`, *optional*, default to `None`):
The scale channel quantization axis, useful for quantizing calculated scale across different axes.
scale_block_quantize (`int`, *optional*, default to `None`):
The scale block size, useful for quantizing each scale channel/axes into blocks.
algorithm (`str`, *optional*, default to `"max"`):
The algorithm to use for quantization, currently only supports `"max"`.
forward_loop (`Callable`, *optional*, default to `None`):
The forward loop function to use for calibration during quantization.
modelopt_config (`dict`, *optional*, default to `None`):
The modelopt config, useful for passing custom configs to modelopt.
disable_conv_quantization (`bool`, *optional*, default to `False`):
If set to `True`, the quantization will be disabled for convolutional layers.
kwargs (`dict[str, Any]`, *optional*):
Additional parameters which are to be used for calibration.
"""
quanttype_to_numbits = {
"FP8": (4, 3),
"INT8": 8,
"INT4": 4,
"NF4": 4,
"NVFP4": (2, 1),
}
quanttype_to_scalingbits = {
"NF4": 8,
"NVFP4": (4, 3),
}
def __init__(
self,
quant_type: str,
modules_to_not_convert: list[str] | None = None,
weight_only: bool = True,
channel_quantize: int | None = None,
block_quantize: int | None = None,
scale_channel_quantize: int | None = None,
scale_block_quantize: int | None = None,
algorithm: str = "max",
forward_loop: Callable | None = None,
modelopt_config: dict | None = None,
disable_conv_quantization: bool = False,
**kwargs,
) -> None:
self.quant_method = QuantizationMethod.MODELOPT
self._normalize_quant_type(quant_type)
self.modules_to_not_convert = modules_to_not_convert
self.weight_only = weight_only
self.channel_quantize = channel_quantize
self.block_quantize = block_quantize
self.calib_cfg = {
"method": algorithm,
# add more options here if needed
}
self.forward_loop = forward_loop
self.scale_channel_quantize = scale_channel_quantize
self.scale_block_quantize = scale_block_quantize
self.modelopt_config = self.get_config_from_quant_type() if not modelopt_config else modelopt_config
self.disable_conv_quantization = disable_conv_quantization
def check_model_patching(self, operation: str = "loading"):
# ModelOpt imports diffusers internally. This is here to prevent circular imports
from modelopt.torch.opt.plugins.huggingface import _PATCHED_CLASSES
if len(_PATCHED_CLASSES) == 0:
warning_msg = (
f"Not {operation} weights in modelopt format. This might cause unreliable behavior."
"Please make sure to run the following code before loading/saving model weights:\n\n"
" from modelopt.torch.opt import enable_huggingface_checkpointing\n"
" enable_huggingface_checkpointing()\n"
)
warnings.warn(warning_msg)
def _normalize_quant_type(self, quant_type: str) -> str:
"""
Validates and normalizes the quantization type string.
Splits the quant_type into weight and activation components, verifies them against supported types, and
replaces unsupported values with safe defaults.
Args:
quant_type (str): The input quantization type string (e.g., 'FP8_INT8').
Returns:
str: A valid quantization type string (e.g., 'FP8_INT8' or 'FP8').
"""
parts = quant_type.split("_")
w_type = parts[0]
act_type = parts[1] if len(parts) > 1 else None
if len(parts) > 2:
logger.warning(f"Quantization type {quant_type} is not supported. Picking FP8_INT8 as default")
w_type = "FP8"
act_type = None
else:
if w_type not in NVIDIAModelOptConfig.quanttype_to_numbits:
logger.warning(f"Weight Quantization type {w_type} is not supported. Picking FP8 as default")
w_type = "FP8"
if act_type is not None and act_type not in NVIDIAModelOptConfig.quanttype_to_numbits:
logger.warning(f"Activation Quantization type {act_type} is not supported. Picking INT8 as default")
act_type = None
self.quant_type = w_type + ("_" + act_type if act_type is not None else "")
def get_config_from_quant_type(self) -> dict[str, Any]:
"""
Get the config from the quantization type.
"""
import modelopt.torch.quantization as mtq
BASE_CONFIG = {
"quant_cfg": {
"*weight_quantizer": {"fake_quant": False},
"*input_quantizer": {},
"*output_quantizer": {"enable": False},
"*q_bmm_quantizer": {},
"*k_bmm_quantizer": {},
"*v_bmm_quantizer": {},
"*softmax_quantizer": {},
**mtq.config._default_disabled_quantizer_cfg,
},
"algorithm": self.calib_cfg,
}
quant_cfg = BASE_CONFIG["quant_cfg"]
if self.weight_only:
for k in quant_cfg:
if "*weight_quantizer" not in k and not quant_cfg[k]:
quant_cfg[k]["enable"] = False
parts = self.quant_type.split("_")
w_type = parts[0]
act_type = parts[1].replace("A", "") if len(parts) > 1 else None
for k in quant_cfg:
if k not in mtq.config._default_disabled_quantizer_cfg and "enable" not in quant_cfg[k]:
if k == "*input_quantizer":
if act_type is not None:
quant_cfg[k]["num_bits"] = NVIDIAModelOptConfig.quanttype_to_numbits[act_type]
continue
quant_cfg[k]["num_bits"] = NVIDIAModelOptConfig.quanttype_to_numbits[w_type]
if self.block_quantize is not None and self.channel_quantize is not None:
quant_cfg["*weight_quantizer"]["block_sizes"] = {self.channel_quantize: self.block_quantize}
quant_cfg["*input_quantizer"]["block_sizes"] = {
self.channel_quantize: self.block_quantize,
"type": "dynamic",
}
elif self.channel_quantize is not None:
quant_cfg["*weight_quantizer"]["axis"] = self.channel_quantize
quant_cfg["*input_quantizer"]["axis"] = self.channel_quantize
quant_cfg["*input_quantizer"]["type"] = "dynamic"
# Only fixed scaling sizes are supported for now in modelopt
if self.scale_channel_quantize is not None and self.scale_block_quantize is not None:
if w_type in NVIDIAModelOptConfig.quanttype_to_scalingbits:
quant_cfg["*weight_quantizer"]["block_sizes"].update(
{
"scale_bits": NVIDIAModelOptConfig.quanttype_to_scalingbits[w_type],
"scale_block_sizes": {self.scale_channel_quantize: self.scale_block_quantize},
}
)
if act_type and act_type in NVIDIAModelOptConfig.quanttype_to_scalingbits:
quant_cfg["*input_quantizer"]["block_sizes"].update(
{
"scale_bits": NVIDIAModelOptConfig.quanttype_to_scalingbits[act_type],
"scale_block_sizes": {self.scale_channel_quantize: self.scale_block_quantize},
}
)
return BASE_CONFIG