Spaces:
Runtime error
Runtime error
# coding=utf-8 | |
# Copyright 2018 The Google AI Language Team Authors, Facebook AI Research authors and The HuggingFace Inc. team. | |
# Copyright (c) 2018, NVIDIA CORPORATION. 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 collections | |
import copy | |
import functools | |
import gc | |
import importlib.metadata | |
import inspect | |
import itertools | |
import json | |
import os | |
import re | |
import shutil | |
import tempfile | |
import warnings | |
from contextlib import contextmanager | |
from dataclasses import dataclass | |
from functools import partial, wraps | |
from threading import Thread | |
from typing import Any, Callable, Dict, List, Optional, Set, Tuple, Union | |
from zipfile import is_zipfile | |
import torch | |
from packaging import version | |
from torch import Tensor, nn | |
from torch.nn import CrossEntropyLoss, Identity | |
from torch.utils.checkpoint import checkpoint | |
from .activations import get_activation | |
from .configuration_utils import PretrainedConfig | |
from .dynamic_module_utils import custom_object_save | |
from .generation import GenerationConfig, GenerationMixin | |
from .integrations import PeftAdapterMixin, deepspeed_config, is_deepspeed_zero3_enabled | |
from .pytorch_utils import ( # noqa: F401 | |
Conv1D, | |
apply_chunking_to_forward, | |
find_pruneable_heads_and_indices, | |
id_tensor_storage, | |
is_torch_greater_or_equal_than_1_13, | |
prune_conv1d_layer, | |
prune_layer, | |
prune_linear_layer, | |
) | |
from .quantizers import AutoHfQuantizer, HfQuantizer | |
from .quantizers.quantizers_utils import get_module_from_name | |
from .safetensors_conversion import auto_conversion | |
from .utils import ( | |
ADAPTER_SAFE_WEIGHTS_NAME, | |
ADAPTER_WEIGHTS_NAME, | |
CONFIG_NAME, | |
DUMMY_INPUTS, | |
FLAX_WEIGHTS_NAME, | |
SAFE_WEIGHTS_INDEX_NAME, | |
SAFE_WEIGHTS_NAME, | |
TF2_WEIGHTS_NAME, | |
TF_WEIGHTS_NAME, | |
WEIGHTS_INDEX_NAME, | |
WEIGHTS_NAME, | |
ContextManagers, | |
ModelOutput, | |
PushToHubMixin, | |
cached_file, | |
copy_func, | |
download_url, | |
extract_commit_hash, | |
has_file, | |
is_accelerate_available, | |
is_bitsandbytes_available, | |
is_flash_attn_2_available, | |
is_offline_mode, | |
is_optimum_available, | |
is_peft_available, | |
is_remote_url, | |
is_safetensors_available, | |
is_torch_sdpa_available, | |
is_torch_xla_available, | |
logging, | |
replace_return_docstrings, | |
strtobool, | |
) | |
from .utils.hub import convert_file_size_to_int, create_and_tag_model_card, get_checkpoint_shard_files | |
from .utils.import_utils import ( | |
ENV_VARS_TRUE_VALUES, | |
is_sagemaker_mp_enabled, | |
is_torch_fx_proxy, | |
is_torchdynamo_compiling, | |
) | |
from .utils.quantization_config import BitsAndBytesConfig, QuantizationMethod | |
XLA_USE_BF16 = os.environ.get("XLA_USE_BF16", "0").upper() | |
XLA_DOWNCAST_BF16 = os.environ.get("XLA_DOWNCAST_BF16", "0").upper() | |
if is_accelerate_available(): | |
from accelerate import dispatch_model, infer_auto_device_map, init_empty_weights | |
from accelerate.hooks import add_hook_to_module | |
from accelerate.utils import ( | |
check_tied_parameters_on_same_device, | |
extract_model_from_parallel, | |
find_tied_parameters, | |
get_balanced_memory, | |
get_max_memory, | |
load_offloaded_weights, | |
offload_weight, | |
save_offload_index, | |
set_module_tensor_to_device, | |
) | |
if is_safetensors_available(): | |
from safetensors import safe_open | |
from safetensors.torch import load_file as safe_load_file | |
from safetensors.torch import save_file as safe_save_file | |
logger = logging.get_logger(__name__) | |
_init_weights = True | |
def is_fsdp_enabled(): | |
return ( | |
torch.distributed.is_available() | |
and torch.distributed.is_initialized() | |
and strtobool(os.environ.get("ACCELERATE_USE_FSDP", "False")) == 1 | |
and strtobool(os.environ.get("FSDP_CPU_RAM_EFFICIENT_LOADING", "False")) == 1 | |
) | |
def is_local_dist_rank_0(): | |
return ( | |
torch.distributed.is_available() | |
and torch.distributed.is_initialized() | |
and int(os.environ.get("LOCAL_RANK", -1)) == 0 | |
) | |
if is_sagemaker_mp_enabled(): | |
import smdistributed.modelparallel.torch as smp | |
from smdistributed.modelparallel import __version__ as SMP_VERSION | |
IS_SAGEMAKER_MP_POST_1_10 = version.parse(SMP_VERSION) >= version.parse("1.10") | |
else: | |
IS_SAGEMAKER_MP_POST_1_10 = False | |
if is_peft_available(): | |
from .utils import find_adapter_config_file | |
TORCH_INIT_FUNCTIONS = { | |
"uniform_": nn.init.uniform_, | |
"normal_": nn.init.normal_, | |
"trunc_normal_": nn.init.trunc_normal_, | |
"constant_": nn.init.constant_, | |
"xavier_uniform_": nn.init.xavier_uniform_, | |
"xavier_normal_": nn.init.xavier_normal_, | |
"kaiming_uniform_": nn.init.kaiming_uniform_, | |
"kaiming_normal_": nn.init.kaiming_normal_, | |
"uniform": nn.init.uniform, | |
"normal": nn.init.normal, | |
"xavier_uniform": nn.init.xavier_uniform, | |
"xavier_normal": nn.init.xavier_normal, | |
"kaiming_uniform": nn.init.kaiming_uniform, | |
"kaiming_normal": nn.init.kaiming_normal, | |
} | |
def no_init_weights(_enable=True): | |
""" | |
Context manager to globally disable weight initialization to speed up loading large models. | |
TODO(Patrick): Delete safety argument `_enable=True` at next major version. . | |
""" | |
global _init_weights | |
old_init_weights = _init_weights | |
if _enable: | |
_init_weights = False | |
def _skip_init(*args, **kwargs): | |
pass | |
# # Save the original initialization functions | |
for name, init_func in TORCH_INIT_FUNCTIONS.items(): | |
setattr(torch.nn.init, name, _skip_init) | |
try: | |
yield | |
finally: | |
_init_weights = old_init_weights | |
if _enable: | |
# # Restore the original initialization functions | |
for name, init_func in TORCH_INIT_FUNCTIONS.items(): | |
setattr(torch.nn.init, name, init_func) | |
def get_parameter_device(parameter: Union[nn.Module, GenerationMixin, "ModuleUtilsMixin"]): | |
try: | |
return next(parameter.parameters()).device | |
except StopIteration: | |
# For nn.DataParallel compatibility in PyTorch 1.5 | |
def find_tensor_attributes(module: nn.Module) -> List[Tuple[str, Tensor]]: | |
tuples = [(k, v) for k, v in module.__dict__.items() if torch.is_tensor(v)] | |
return tuples | |
gen = parameter._named_members(get_members_fn=find_tensor_attributes) | |
first_tuple = next(gen) | |
return first_tuple[1].device | |
def get_first_parameter_dtype(parameter: Union[nn.Module, GenerationMixin, "ModuleUtilsMixin"]): | |
""" | |
Returns the first parameter dtype (can be non-floating) or asserts if none were found. | |
""" | |
try: | |
return next(parameter.parameters()).dtype | |
except StopIteration: | |
# For nn.DataParallel compatibility in PyTorch > 1.5 | |
def find_tensor_attributes(module: nn.Module) -> List[Tuple[str, Tensor]]: | |
tuples = [(k, v) for k, v in module.__dict__.items() if torch.is_tensor(v)] | |
return tuples | |
gen = parameter._named_members(get_members_fn=find_tensor_attributes) | |
first_tuple = next(gen) | |
return first_tuple[1].dtype | |
def get_parameter_dtype(parameter: Union[nn.Module, GenerationMixin, "ModuleUtilsMixin"]): | |
""" | |
Returns the first found floating dtype in parameters if there is one, otherwise returns the last dtype it found. | |
""" | |
last_dtype = None | |
for t in parameter.parameters(): | |
last_dtype = t.dtype | |
if t.is_floating_point(): | |
# Adding fix for https://github.com/pytorch/xla/issues/4152 | |
# Fixes issue where the model code passes a value that is out of range for XLA_USE_BF16=1 | |
# and XLA_DOWNCAST_BF16=1 so the conversion would cast it to -inf | |
# NOTE: `is_torch_xla_available()` is checked last as it induces a graph break in torch dynamo | |
if XLA_USE_BF16 in ENV_VARS_TRUE_VALUES and is_torch_xla_available(): | |
return torch.bfloat16 | |
if XLA_DOWNCAST_BF16 in ENV_VARS_TRUE_VALUES and is_torch_xla_available(): | |
if t.dtype == torch.float: | |
return torch.bfloat16 | |
if t.dtype == torch.double: | |
return torch.float32 | |
return t.dtype | |
if last_dtype is not None: | |
# if no floating dtype was found return whatever the first dtype is | |
return last_dtype | |
# For nn.DataParallel compatibility in PyTorch > 1.5 | |
def find_tensor_attributes(module: nn.Module) -> List[Tuple[str, Tensor]]: | |
tuples = [(k, v) for k, v in module.__dict__.items() if torch.is_tensor(v)] | |
return tuples | |
gen = parameter._named_members(get_members_fn=find_tensor_attributes) | |
last_tuple = None | |
for tuple in gen: | |
last_tuple = tuple | |
if tuple[1].is_floating_point(): | |
return tuple[1].dtype | |
if last_tuple is not None: | |
# fallback to the last dtype | |
return last_tuple[1].dtype | |
# fallback to buffer dtype | |
for t in parameter.buffers(): | |
last_dtype = t.dtype | |
if t.is_floating_point(): | |
return t.dtype | |
return last_dtype | |
def get_state_dict_float_dtype(state_dict): | |
""" | |
Returns the first found floating dtype in `state_dict` or asserts if none were found. | |
""" | |
for t in state_dict.values(): | |
if t.is_floating_point(): | |
return t.dtype | |
raise ValueError("couldn't find any floating point dtypes in state_dict") | |
def get_state_dict_dtype(state_dict): | |
""" | |
Returns the first found floating dtype in `state_dict` if there is one, otherwise returns the first dtype. | |
""" | |
for t in state_dict.values(): | |
if t.is_floating_point(): | |
return t.dtype | |
# if no floating dtype was found return whatever the first dtype is | |
else: | |
return next(state_dict.values()).dtype | |
def dtype_byte_size(dtype): | |
""" | |
Returns the size (in bytes) occupied by one parameter of type `dtype`. | |
Example: | |
```py | |
>>> dtype_byte_size(torch.float32) | |
4 | |
``` | |
""" | |
if dtype == torch.bool: | |
return 1 / 8 | |
bit_search = re.search(r"[^\d](\d+)$", str(dtype)) | |
if bit_search is None: | |
raise ValueError(f"`dtype` is not a valid dtype: {dtype}.") | |
bit_size = int(bit_search.groups()[0]) | |
return bit_size // 8 | |
def shard_checkpoint( | |
state_dict: Dict[str, torch.Tensor], max_shard_size: Union[int, str] = "10GB", weights_name: str = WEIGHTS_NAME | |
): | |
""" | |
Splits a model state dictionary in sub-checkpoints so that the final size of each sub-checkpoint does not exceed a | |
given size. | |
The sub-checkpoints are determined by iterating through the `state_dict` in the order of its keys, so there is no | |
optimization made to make each sub-checkpoint as close as possible to the maximum size passed. For example, if the | |
limit is 10GB and we have weights of sizes [6GB, 6GB, 2GB, 6GB, 2GB, 2GB] they will get sharded as [6GB], [6+2GB], | |
[6+2+2GB] and not [6+2+2GB], [6+2GB], [6GB]. | |
<Tip warning={true}> | |
If one of the model's weight is bigger than `max_shard_size`, it will end up in its own sub-checkpoint which will | |
have a size greater than `max_shard_size`. | |
</Tip> | |
Args: | |
state_dict (`Dict[str, torch.Tensor]`): The state dictionary of a model to save. | |
max_shard_size (`int` or `str`, *optional*, defaults to `"10GB"`): | |
The maximum size of each sub-checkpoint. If expressed as a string, needs to be digits followed by a unit | |
(like `"5MB"`). | |
weights_name (`str`, *optional*, defaults to `"pytorch_model.bin"`): | |
The name of the model save file. | |
""" | |
max_shard_size = convert_file_size_to_int(max_shard_size) | |
sharded_state_dicts = [{}] | |
last_block_size = 0 | |
total_size = 0 | |
storage_id_to_block = {} | |
for key, weight in state_dict.items(): | |
# when bnb serialization is used the weights in the state dict can be strings | |
# check: https://github.com/huggingface/transformers/pull/24416 for more details | |
if isinstance(weight, str): | |
continue | |
else: | |
storage_id = id_tensor_storage(weight) | |
# If a `weight` shares the same underlying storage as another tensor, we put `weight` in the same `block` | |
if storage_id in storage_id_to_block: | |
block_id = storage_id_to_block[storage_id] | |
sharded_state_dicts[block_id][key] = weight | |
continue | |
weight_size = weight.numel() * dtype_byte_size(weight.dtype) | |
# If this weight is going to tip up over the maximal size, we split, but only if we have put at least one | |
# weight in the current shard. | |
if last_block_size + weight_size > max_shard_size and len(sharded_state_dicts[-1]) > 0: | |
sharded_state_dicts.append({}) | |
last_block_size = 0 | |
sharded_state_dicts[-1][key] = weight | |
last_block_size += weight_size | |
total_size += weight_size | |
storage_id_to_block[storage_id] = len(sharded_state_dicts) - 1 | |
# If we only have one shard, we return it | |
if len(sharded_state_dicts) == 1: | |
return {weights_name: sharded_state_dicts[0]}, None | |
# Otherwise, let's build the index | |
weight_map = {} | |
shards = {} | |
for idx, shard in enumerate(sharded_state_dicts): | |
shard_file = weights_name.replace(".bin", f"-{idx+1:05d}-of-{len(sharded_state_dicts):05d}.bin") | |
shard_file = shard_file.replace( | |
".safetensors", f"-{idx + 1:05d}-of-{len(sharded_state_dicts):05d}.safetensors" | |
) | |
shards[shard_file] = shard | |
for key in shard.keys(): | |
weight_map[key] = shard_file | |
# Add the metadata | |
metadata = {"total_size": total_size} | |
index = {"metadata": metadata, "weight_map": weight_map} | |
return shards, index | |
def load_sharded_checkpoint(model, folder, strict=True, prefer_safe=True): | |
""" | |
This is the same as | |
[`torch.nn.Module.load_state_dict`](https://pytorch.org/docs/stable/generated/torch.nn.Module.html?highlight=load_state_dict#torch.nn.Module.load_state_dict) | |
but for a sharded checkpoint. | |
This load is performed efficiently: each checkpoint shard is loaded one by one in RAM and deleted after being | |
loaded in the model. | |
Args: | |
model (`torch.nn.Module`): The model in which to load the checkpoint. | |
folder (`str` or `os.PathLike`): A path to a folder containing the sharded checkpoint. | |
strict (`bool`, *optional`, defaults to `True`): | |
Whether to strictly enforce that the keys in the model state dict match the keys in the sharded checkpoint. | |
prefer_safe (`bool`, *optional*, defaults to `False`) | |
If both safetensors and PyTorch save files are present in checkpoint and `prefer_safe` is True, the | |
safetensors files will be loaded. Otherwise, PyTorch files are always loaded when possible. | |
Returns: | |
`NamedTuple`: A named tuple with `missing_keys` and `unexpected_keys` fields | |
- `missing_keys` is a list of str containing the missing keys | |
- `unexpected_keys` is a list of str containing the unexpected keys | |
""" | |
# Load the index | |
index_file = os.path.join(folder, WEIGHTS_INDEX_NAME) | |
safe_index_file = os.path.join(folder, SAFE_WEIGHTS_INDEX_NAME) | |
index_present = os.path.isfile(index_file) | |
safe_index_present = os.path.isfile(safe_index_file) | |
if not index_present and not (safe_index_present and is_safetensors_available()): | |
filenames = ( | |
(WEIGHTS_INDEX_NAME, SAFE_WEIGHTS_INDEX_NAME) if is_safetensors_available() else (WEIGHTS_INDEX_NAME,) | |
) | |
raise ValueError(f"Can't find a checkpoint index ({' or '.join(filenames)}) in {folder}.") | |
load_safe = False | |
if safe_index_present: | |
if prefer_safe: | |
if is_safetensors_available(): | |
load_safe = True # load safe due to preference | |
else: | |
logger.warning( | |
f"Cannot load sharded checkpoint at {folder} safely since safetensors is not installed!" | |
) | |
elif not index_present: | |
load_safe = True # load safe since we have no other choice | |
load_index = safe_index_file if load_safe else index_file | |
with open(load_index, "r", encoding="utf-8") as f: | |
index = json.load(f) | |
shard_files = list(set(index["weight_map"].values())) | |
# If strict=True, error before loading any of the state dicts. | |
loaded_keys = index["weight_map"].keys() | |
model_keys = model.state_dict().keys() | |
missing_keys = [key for key in model_keys if key not in loaded_keys] | |
unexpected_keys = [key for key in loaded_keys if key not in model_keys] | |
if strict and (len(missing_keys) > 0 or len(unexpected_keys) > 0): | |
error_message = f"Error(s) in loading state_dict for {model.__class__.__name__}" | |
if len(missing_keys) > 0: | |
str_missing_keys = ",".join([f'"{k}"' for k in missing_keys]) | |
error_message += f"\nMissing key(s): {str_missing_keys}." | |
if len(unexpected_keys) > 0: | |
str_unexpected_keys = ",".join([f'"{k}"' for k in unexpected_keys]) | |
error_message += f"\nMissing key(s): {str_unexpected_keys}." | |
raise RuntimeError(error_message) | |
weights_only_kwarg = {"weights_only": True} if is_torch_greater_or_equal_than_1_13 else {} | |
loader = safe_load_file if load_safe else partial(torch.load, map_location="cpu", **weights_only_kwarg) | |
for shard_file in shard_files: | |
state_dict = loader(os.path.join(folder, shard_file)) | |
model.load_state_dict(state_dict, strict=False) | |
# Make sure memory is freed before we load the next state dict. | |
del state_dict | |
gc.collect() | |
# Return the same thing as PyTorch load_state_dict function. | |
return torch.nn.modules.module._IncompatibleKeys(missing_keys, unexpected_keys) | |
def load_state_dict(checkpoint_file: Union[str, os.PathLike], is_quantized: bool = False): | |
""" | |
Reads a PyTorch checkpoint file, returning properly formatted errors if they arise. | |
""" | |
if checkpoint_file.endswith(".safetensors") and is_safetensors_available(): | |
# Check format of the archive | |
with safe_open(checkpoint_file, framework="pt") as f: | |
metadata = f.metadata() | |
if metadata.get("format") not in ["pt", "tf", "flax", "mlx"]: | |
raise OSError( | |
f"The safetensors archive passed at {checkpoint_file} does not contain the valid metadata. Make sure " | |
"you save your model with the `save_pretrained` method." | |
) | |
return safe_load_file(checkpoint_file) | |
try: | |
if ( | |
(is_deepspeed_zero3_enabled() and torch.distributed.is_initialized() and torch.distributed.get_rank() > 0) | |
or (is_fsdp_enabled() and not is_local_dist_rank_0()) | |
) and not is_quantized: | |
map_location = "meta" | |
else: | |
map_location = "cpu" | |
extra_args = {} | |
# mmap can only be used with files serialized with zipfile-based format. | |
if ( | |
isinstance(checkpoint_file, str) | |
and map_location != "meta" | |
and version.parse(torch.__version__) >= version.parse("2.1.0") | |
and is_zipfile(checkpoint_file) | |
): | |
extra_args = {"mmap": True} | |
weights_only_kwarg = {"weights_only": True} if is_torch_greater_or_equal_than_1_13 else {} | |
return torch.load( | |
checkpoint_file, | |
map_location=map_location, | |
**weights_only_kwarg, | |
**extra_args, | |
) | |
except Exception as e: | |
try: | |
with open(checkpoint_file) as f: | |
if f.read(7) == "version": | |
raise OSError( | |
"You seem to have cloned a repository without having git-lfs installed. Please install " | |
"git-lfs and run `git lfs install` followed by `git lfs pull` in the folder " | |
"you cloned." | |
) | |
else: | |
raise ValueError( | |
f"Unable to locate the file {checkpoint_file} which is necessary to load this pretrained " | |
"model. Make sure you have saved the model properly." | |
) from e | |
except (UnicodeDecodeError, ValueError): | |
raise OSError( | |
f"Unable to load weights from pytorch checkpoint file for '{checkpoint_file}' " | |
f"at '{checkpoint_file}'. " | |
"If you tried to load a PyTorch model from a TF 2.0 checkpoint, please set from_tf=True." | |
) | |
def set_initialized_submodules(model, state_dict_keys): | |
""" | |
Sets the `_is_hf_initialized` flag in all submodules of a given model when all its weights are in the loaded state | |
dict. | |
""" | |
not_initialized_submodules = {} | |
for module_name, module in model.named_modules(): | |
loaded_keys = {k.replace(f"{module_name}.", "") for k in state_dict_keys if k.startswith(f"{module_name}.")} | |
if loaded_keys.issuperset(module.state_dict()): | |
module._is_hf_initialized = True | |
else: | |
not_initialized_submodules[module_name] = module | |
return not_initialized_submodules | |
def _end_ptr(tensor: torch.Tensor) -> int: | |
# extract the end of the pointer if the tensor is a slice of a bigger tensor | |
if tensor.nelement(): | |
stop = tensor.view(-1)[-1].data_ptr() + tensor.element_size() | |
else: | |
stop = tensor.data_ptr() | |
return stop | |
def _get_tied_weight_keys(module: nn.Module, prefix=""): | |
tied_weight_keys = [] | |
if getattr(module, "_tied_weights_keys", None) is not None: | |
names = [f"{prefix}.{k}" if prefix else k for k in module._tied_weights_keys] | |
tied_weight_keys.extend(names) | |
if getattr(module, "_dynamic_tied_weights_keys", None) is not None: | |
names = [f"{prefix}.{k}" if prefix else k for k in module._dynamic_tied_weights_keys] | |
tied_weight_keys.extend(names) | |
for name, submodule in module.named_children(): | |
local_prefix = f"{prefix}.{name}" if prefix else name | |
tied_weight_keys.extend(_get_tied_weight_keys(submodule, prefix=local_prefix)) | |
return tied_weight_keys | |
def _find_disjoint(tensors: List[Set[str]], state_dict: Dict[str, torch.Tensor]) -> Tuple[List[Set[str]], List[str]]: | |
filtered_tensors = [] | |
for shared in tensors: | |
if len(shared) < 2: | |
filtered_tensors.append(shared) | |
continue | |
areas = [] | |
for name in shared: | |
tensor = state_dict[name] | |
areas.append((tensor.data_ptr(), _end_ptr(tensor), name)) | |
areas.sort() | |
_, last_stop, last_name = areas[0] | |
filtered_tensors.append({last_name}) | |
for start, stop, name in areas[1:]: | |
if start >= last_stop: | |
filtered_tensors.append({name}) | |
else: | |
filtered_tensors[-1].add(name) | |
last_stop = stop | |
disjoint_tensors = [] | |
shared_tensors = [] | |
for tensors in filtered_tensors: | |
if len(tensors) == 1: | |
disjoint_tensors.append(tensors.pop()) | |
else: | |
shared_tensors.append(tensors) | |
return shared_tensors, disjoint_tensors | |
def _find_identical(tensors: List[Set[str]], state_dict: Dict[str, torch.Tensor]) -> Tuple[List[Set[str]], Set[str]]: | |
shared_tensors = [] | |
identical = [] | |
for shared in tensors: | |
if len(shared) < 2: | |
continue | |
areas = collections.defaultdict(set) | |
for name in shared: | |
tensor = state_dict[name] | |
area = (tensor.device, tensor.data_ptr(), _end_ptr(tensor)) | |
areas[area].add(name) | |
if len(areas) == 1: | |
identical.append(shared) | |
else: | |
shared_tensors.append(shared) | |
return shared_tensors, identical | |
def _load_state_dict_into_model(model_to_load, state_dict, start_prefix): | |
# Convert old format to new format if needed from a PyTorch state_dict | |
old_keys = [] | |
new_keys = [] | |
for key in state_dict.keys(): | |
new_key = None | |
if "gamma" in key: | |
new_key = key.replace("gamma", "weight") | |
if "beta" in key: | |
new_key = key.replace("beta", "bias") | |
if new_key: | |
old_keys.append(key) | |
new_keys.append(new_key) | |
for old_key, new_key in zip(old_keys, new_keys): | |
state_dict[new_key] = state_dict.pop(old_key) | |
# copy state_dict so _load_from_state_dict can modify it | |
metadata = getattr(state_dict, "_metadata", None) | |
state_dict = state_dict.copy() | |
if metadata is not None: | |
state_dict._metadata = metadata | |
error_msgs = [] | |
# PyTorch's `_load_from_state_dict` does not copy parameters in a module's descendants | |
# so we need to apply the function recursively. | |
def load(module: nn.Module, state_dict, prefix=""): | |
local_metadata = {} if metadata is None else metadata.get(prefix[:-1], {}) | |
args = (state_dict, prefix, local_metadata, True, [], [], error_msgs) | |
# Parameters of module and children will start with prefix. We can exit early if there are none in this | |
# state_dict | |
if len([key for key in state_dict if key.startswith(prefix)]) > 0: | |
if is_deepspeed_zero3_enabled(): | |
import deepspeed | |
# In sharded models, each shard has only part of the full state_dict, so only gather | |
# parameters that are in the current state_dict. | |
named_parameters = dict(module.named_parameters(prefix=prefix[:-1], recurse=False)) | |
params_to_gather = [named_parameters[k] for k in state_dict.keys() if k in named_parameters] | |
if len(params_to_gather) > 0: | |
# because zero3 puts placeholders in model params, this context | |
# manager gathers (unpartitions) the params of the current layer, then loads from | |
# the state dict and then re-partitions them again | |
with deepspeed.zero.GatheredParameters(params_to_gather, modifier_rank=0): | |
if torch.distributed.get_rank() == 0: | |
module._load_from_state_dict(*args) | |
else: | |
module._load_from_state_dict(*args) | |
for name, child in module._modules.items(): | |
if child is not None: | |
load(child, state_dict, prefix + name + ".") | |
load(model_to_load, state_dict, prefix=start_prefix) | |
# Delete `state_dict` so it could be collected by GC earlier. Note that `state_dict` is a copy of the argument, so | |
# it's safe to delete it. | |
del state_dict | |
return error_msgs | |
def find_submodule_and_param_name(model, long_key, start_prefix): | |
""" | |
A helper util to find the last sub-module and the param/buffer name. If `start_prefix` is supplied it'll be removed | |
from the start of the key | |
""" | |
if len(start_prefix) > 0 and long_key.startswith(start_prefix): | |
long_key = ".".join(long_key.split(".")[1:]) | |
split_key = long_key.split(".") | |
submodule = model | |
while len(split_key) > 1: | |
if hasattr(submodule, split_key[0]): | |
submodule = getattr(submodule, split_key[0]) | |
del split_key[0] | |
else: | |
submodule = None | |
break | |
if submodule == model: | |
submodule = None | |
return submodule, split_key[0] | |
def _move_model_to_meta(model, loaded_state_dict_keys, start_prefix): | |
""" | |
Moves `loaded_state_dict_keys` in model to meta device which frees up the memory taken by those params. | |
`start_prefix` is used for models which insert their name into model keys, e.g. `bert` in | |
`bert.pooler.dense.weight` | |
""" | |
# dematerialize param storage for keys that are going to be replaced by state_dict, by | |
# putting those on the meta device | |
for k in loaded_state_dict_keys: | |
submodule, param_name = find_submodule_and_param_name(model, k, start_prefix) | |
if submodule is not None: | |
# selectively switch to the meta device only those params/buffers that will | |
# be next replaced from state_dict. This a complex way to do p.to_("meta") | |
# since we have no in-place to_ for tensors. | |
new_val = getattr(submodule, param_name) | |
if isinstance(new_val, torch.nn.Parameter): | |
# isinstance returns False for Params on meta device, so switch after the check | |
new_val = torch.nn.Parameter(new_val.to("meta")) | |
else: | |
new_val = new_val.to("meta") | |
setattr(submodule, param_name, new_val) | |
def _load_state_dict_into_meta_model( | |
model, | |
state_dict, | |
loaded_state_dict_keys, # left for now but could be removed, see below | |
start_prefix, | |
expected_keys, | |
device_map=None, | |
offload_folder=None, | |
offload_index=None, | |
state_dict_folder=None, | |
state_dict_index=None, | |
dtype=None, | |
hf_quantizer=None, | |
is_safetensors=False, | |
keep_in_fp32_modules=None, | |
unexpected_keys=None, # passing `unexpected` for cleanup from quantization items | |
): | |
""" | |
This is somewhat similar to `_load_state_dict_into_model`, but deals with a model that has some or all of its | |
params on a `meta` device. It replaces the model params with the data from the `state_dict`, while moving the | |
params back to the normal device, but only for `loaded_state_dict_keys`. | |
`start_prefix` is used for models which insert their name into model keys, e.g. `bert` in | |
`bert.pooler.dense.weight` | |
""" | |
# XXX: remaining features to implement to be fully compatible with _load_state_dict_into_model | |
# - deepspeed zero 3 support | |
# - need to copy metadata if any - see _load_state_dict_into_model | |
# - handling error_msgs - mimicking the error handling in module._load_from_state_dict() | |
# - Is there a situation where some keys aren't in `loaded_state_dict_keys` and in which case | |
# they won't get loaded. | |
error_msgs = [] | |
old_keys = [] | |
new_keys = [] | |
is_quantized = hf_quantizer is not None | |
for key in state_dict.keys(): | |
new_key = None | |
if "gamma" in key: | |
new_key = key.replace("gamma", "weight") | |
if "beta" in key: | |
new_key = key.replace("beta", "bias") | |
if new_key: | |
old_keys.append(key) | |
new_keys.append(new_key) | |
for old_key, new_key in zip(old_keys, new_keys): | |
state_dict[new_key] = state_dict.pop(old_key) | |
for param_name, param in state_dict.items(): | |
# First part of the test is always true as load_state_dict_keys always contains state_dict keys. | |
if param_name not in loaded_state_dict_keys or param_name not in expected_keys: | |
continue | |
if param_name.startswith(start_prefix): | |
param_name = param_name[len(start_prefix) :] | |
module_name = param_name | |
set_module_kwargs = {} | |
# We convert floating dtypes to the `dtype` passed. We want to keep the buffers/params | |
# in int/uint/bool and not cast them. | |
if dtype is not None and torch.is_floating_point(param): | |
if ( | |
keep_in_fp32_modules is not None | |
and any( | |
module_to_keep_in_fp32 in param_name.split(".") for module_to_keep_in_fp32 in keep_in_fp32_modules | |
) | |
and dtype == torch.float16 | |
): | |
param = param.to(torch.float32) | |
# For backward compatibility with older versions of `accelerate` | |
# TODO: @sgugger replace this check with version check at the next `accelerate` release | |
if "dtype" in list(inspect.signature(set_module_tensor_to_device).parameters): | |
set_module_kwargs["dtype"] = torch.float32 | |
else: | |
param = param.to(dtype) | |
# For compatibility with PyTorch load_state_dict which converts state dict dtype to existing dtype in model, and which | |
# uses `param.copy_(input_param)` that preserves the contiguity of the parameter in the model. | |
# Reference: https://github.com/pytorch/pytorch/blob/db79ceb110f6646523019a59bbd7b838f43d4a86/torch/nn/modules/module.py#L2040C29-L2040C29 | |
old_param = model | |
splits = param_name.split(".") | |
for split in splits: | |
old_param = getattr(old_param, split) | |
if old_param is None: | |
break | |
if old_param is not None: | |
if dtype is None: | |
param = param.to(old_param.dtype) | |
if old_param.is_contiguous(): | |
param = param.contiguous() | |
set_module_kwargs["value"] = param | |
if device_map is None: | |
param_device = "cpu" | |
else: | |
# find next higher level module that is defined in device_map: | |
# bert.lm_head.weight -> bert.lm_head -> bert -> '' | |
while len(module_name) > 0 and module_name not in device_map: | |
module_name = ".".join(module_name.split(".")[:-1]) | |
if module_name == "" and "" not in device_map: | |
# TODO: group all errors and raise at the end. | |
raise ValueError(f"{param_name} doesn't have any device set.") | |
param_device = device_map[module_name] | |
if param_device == "disk": | |
if not is_safetensors: | |
offload_index = offload_weight(param, param_name, offload_folder, offload_index) | |
elif param_device == "cpu" and state_dict_index is not None: | |
state_dict_index = offload_weight(param, param_name, state_dict_folder, state_dict_index) | |
elif ( | |
not is_quantized | |
or (not hf_quantizer.requires_parameters_quantization) | |
or ( | |
not hf_quantizer.check_quantized_param( | |
model, param, param_name, state_dict, param_device=param_device, device_map=device_map | |
) | |
) | |
): | |
# For backward compatibility with older versions of `accelerate` and for non-quantized params | |
set_module_tensor_to_device(model, param_name, param_device, **set_module_kwargs) | |
else: | |
hf_quantizer.create_quantized_param(model, param, param_name, param_device, state_dict, unexpected_keys) | |
# For quantized modules with FSDP/DeepSpeed Stage 3, we need to quantize the parameter on the GPU | |
# and then cast it to CPU to avoid excessive memory usage on each GPU | |
# in comparison to the sharded model across GPUs. | |
if is_fsdp_enabled() or is_deepspeed_zero3_enabled(): | |
module, tensor_name = get_module_from_name(model, param_name) | |
value = getattr(module, tensor_name) | |
value = type(value)(value.data.to("cpu"), **value.__dict__) | |
setattr(module, tensor_name, value) | |
# TODO: consider removing used param_parts from state_dict before return | |
return error_msgs, offload_index, state_dict_index | |
def _add_variant(weights_name: str, variant: Optional[str] = None) -> str: | |
if variant is not None: | |
splits = weights_name.split(".") | |
splits = splits[:-1] + [variant] + splits[-1:] | |
weights_name = ".".join(splits) | |
return weights_name | |
class ModuleUtilsMixin: | |
""" | |
A few utilities for `torch.nn.Modules`, to be used as a mixin. | |
""" | |
def _hook_rss_memory_pre_forward(module, *args, **kwargs): | |
try: | |
import psutil | |
except ImportError: | |
raise ImportError("You need to install psutil (pip install psutil) to use memory tracing.") | |
process = psutil.Process(os.getpid()) | |
mem = process.memory_info() | |
module.mem_rss_pre_forward = mem.rss | |
return None | |
def _hook_rss_memory_post_forward(module, *args, **kwargs): | |
try: | |
import psutil | |
except ImportError: | |
raise ImportError("You need to install psutil (pip install psutil) to use memory tracing.") | |
process = psutil.Process(os.getpid()) | |
mem = process.memory_info() | |
module.mem_rss_post_forward = mem.rss | |
mem_rss_diff = module.mem_rss_post_forward - module.mem_rss_pre_forward | |
module.mem_rss_diff = mem_rss_diff + (module.mem_rss_diff if hasattr(module, "mem_rss_diff") else 0) | |
return None | |
def add_memory_hooks(self): | |
""" | |
Add a memory hook before and after each sub-module forward pass to record increase in memory consumption. | |
Increase in memory consumption is stored in a `mem_rss_diff` attribute for each module and can be reset to zero | |
with `model.reset_memory_hooks_state()`. | |
""" | |
for module in self.modules(): | |
module.register_forward_pre_hook(self._hook_rss_memory_pre_forward) | |
module.register_forward_hook(self._hook_rss_memory_post_forward) | |
self.reset_memory_hooks_state() | |
def reset_memory_hooks_state(self): | |
""" | |
Reset the `mem_rss_diff` attribute of each module (see [`~modeling_utils.ModuleUtilsMixin.add_memory_hooks`]). | |
""" | |
for module in self.modules(): | |
module.mem_rss_diff = 0 | |
module.mem_rss_post_forward = 0 | |
module.mem_rss_pre_forward = 0 | |
def device(self) -> torch.device: | |
""" | |
`torch.device`: The device on which the module is (assuming that all the module parameters are on the same | |
device). | |
""" | |
return get_parameter_device(self) | |
def dtype(self) -> torch.dtype: | |
""" | |
`torch.dtype`: The dtype of the module (assuming that all the module parameters have the same dtype). | |
""" | |
return get_parameter_dtype(self) | |
def invert_attention_mask(self, encoder_attention_mask: Tensor) -> Tensor: | |
""" | |
Invert an attention mask (e.g., switches 0. and 1.). | |
Args: | |
encoder_attention_mask (`torch.Tensor`): An attention mask. | |
Returns: | |
`torch.Tensor`: The inverted attention mask. | |
""" | |
if encoder_attention_mask.dim() == 3: | |
encoder_extended_attention_mask = encoder_attention_mask[:, None, :, :] | |
if encoder_attention_mask.dim() == 2: | |
encoder_extended_attention_mask = encoder_attention_mask[:, None, None, :] | |
# T5 has a mask that can compare sequence ids, we can simulate this here with this transposition | |
# Cf. https://github.com/tensorflow/mesh/blob/8d2465e9bc93129b913b5ccc6a59aa97abd96ec6/mesh_tensorflow | |
# /transformer/transformer_layers.py#L270 | |
# encoder_extended_attention_mask = (encoder_extended_attention_mask == | |
# encoder_extended_attention_mask.transpose(-1, -2)) | |
encoder_extended_attention_mask = encoder_extended_attention_mask.to(dtype=self.dtype) # fp16 compatibility | |
encoder_extended_attention_mask = (1.0 - encoder_extended_attention_mask) * torch.finfo(self.dtype).min | |
return encoder_extended_attention_mask | |
def create_extended_attention_mask_for_decoder(input_shape, attention_mask, device=None): | |
if device is not None: | |
warnings.warn( | |
"The `device` argument is deprecated and will be removed in v5 of Transformers.", FutureWarning | |
) | |
else: | |
device = attention_mask.device | |
batch_size, seq_length = input_shape | |
seq_ids = torch.arange(seq_length, device=device) | |
causal_mask = seq_ids[None, None, :].repeat(batch_size, seq_length, 1) <= seq_ids[None, :, None] | |
# in case past_key_values are used we need to add a prefix ones mask to the causal mask | |
# causal and attention masks must have same type with pytorch version < 1.3 | |
causal_mask = causal_mask.to(attention_mask.dtype) | |
if causal_mask.shape[1] < attention_mask.shape[1]: | |
prefix_seq_len = attention_mask.shape[1] - causal_mask.shape[1] | |
causal_mask = torch.cat( | |
[ | |
torch.ones((batch_size, seq_length, prefix_seq_len), device=device, dtype=causal_mask.dtype), | |
causal_mask, | |
], | |
axis=-1, | |
) | |
extended_attention_mask = causal_mask[:, None, :, :] * attention_mask[:, None, None, :] | |
return extended_attention_mask | |
def get_extended_attention_mask( | |
self, attention_mask: Tensor, input_shape: Tuple[int], device: torch.device = None, dtype: torch.float = None | |
) -> Tensor: | |
""" | |
Makes broadcastable attention and causal masks so that future and masked tokens are ignored. | |
Arguments: | |
attention_mask (`torch.Tensor`): | |
Mask with ones indicating tokens to attend to, zeros for tokens to ignore. | |
input_shape (`Tuple[int]`): | |
The shape of the input to the model. | |
Returns: | |
`torch.Tensor` The extended attention mask, with a the same dtype as `attention_mask.dtype`. | |
""" | |
if dtype is None: | |
dtype = self.dtype | |
if not (attention_mask.dim() == 2 and self.config.is_decoder): | |
# show warning only if it won't be shown in `create_extended_attention_mask_for_decoder` | |
if device is not None: | |
warnings.warn( | |
"The `device` argument is deprecated and will be removed in v5 of Transformers.", FutureWarning | |
) | |
# We can provide a self-attention mask of dimensions [batch_size, from_seq_length, to_seq_length] | |
# ourselves in which case we just need to make it broadcastable to all heads. | |
if attention_mask.dim() == 3: | |
extended_attention_mask = attention_mask[:, None, :, :] | |
elif attention_mask.dim() == 2: | |
# Provided a padding mask of dimensions [batch_size, seq_length] | |
# - if the model is a decoder, apply a causal mask in addition to the padding mask | |
# - if the model is an encoder, make the mask broadcastable to [batch_size, num_heads, seq_length, seq_length] | |
if self.config.is_decoder: | |
extended_attention_mask = ModuleUtilsMixin.create_extended_attention_mask_for_decoder( | |
input_shape, attention_mask, device | |
) | |
else: | |
extended_attention_mask = attention_mask[:, None, None, :] | |
else: | |
raise ValueError( | |
f"Wrong shape for input_ids (shape {input_shape}) or attention_mask (shape {attention_mask.shape})" | |
) | |
# Since attention_mask is 1.0 for positions we want to attend and 0.0 for | |
# masked positions, this operation will create a tensor which is 0.0 for | |
# positions we want to attend and the dtype's smallest value for masked positions. | |
# Since we are adding it to the raw scores before the softmax, this is | |
# effectively the same as removing these entirely. | |
extended_attention_mask = extended_attention_mask.to(dtype=dtype) # fp16 compatibility | |
extended_attention_mask = (1.0 - extended_attention_mask) * torch.finfo(dtype).min | |
return extended_attention_mask | |
def get_head_mask( | |
self, head_mask: Optional[Tensor], num_hidden_layers: int, is_attention_chunked: bool = False | |
) -> Tensor: | |
""" | |
Prepare the head mask if needed. | |
Args: | |
head_mask (`torch.Tensor` with shape `[num_heads]` or `[num_hidden_layers x num_heads]`, *optional*): | |
The mask indicating if we should keep the heads or not (1.0 for keep, 0.0 for discard). | |
num_hidden_layers (`int`): | |
The number of hidden layers in the model. | |
is_attention_chunked (`bool`, *optional*, defaults to `False`): | |
Whether or not the attentions scores are computed by chunks or not. | |
Returns: | |
`torch.Tensor` with shape `[num_hidden_layers x batch x num_heads x seq_length x seq_length]` or list with | |
`[None]` for each layer. | |
""" | |
if head_mask is not None: | |
head_mask = self._convert_head_mask_to_5d(head_mask, num_hidden_layers) | |
if is_attention_chunked is True: | |
head_mask = head_mask.unsqueeze(-1) | |
else: | |
head_mask = [None] * num_hidden_layers | |
return head_mask | |
def _convert_head_mask_to_5d(self, head_mask, num_hidden_layers): | |
"""-> [num_hidden_layers x batch x num_heads x seq_length x seq_length]""" | |
if head_mask.dim() == 1: | |
head_mask = head_mask.unsqueeze(0).unsqueeze(0).unsqueeze(-1).unsqueeze(-1) | |
head_mask = head_mask.expand(num_hidden_layers, -1, -1, -1, -1) | |
elif head_mask.dim() == 2: | |
head_mask = head_mask.unsqueeze(1).unsqueeze(-1).unsqueeze(-1) # We can specify head_mask for each layer | |
assert head_mask.dim() == 5, f"head_mask.dim != 5, instead {head_mask.dim()}" | |
head_mask = head_mask.to(dtype=self.dtype) # switch to float if need + fp16 compatibility | |
return head_mask | |
def num_parameters(self, only_trainable: bool = False, exclude_embeddings: bool = False) -> int: | |
""" | |
Get number of (optionally, trainable or non-embeddings) parameters in the module. | |
Args: | |
only_trainable (`bool`, *optional*, defaults to `False`): | |
Whether or not to return only the number of trainable parameters | |
exclude_embeddings (`bool`, *optional*, defaults to `False`): | |
Whether or not to return only the number of non-embeddings parameters | |
Returns: | |
`int`: The number of parameters. | |
""" | |
if exclude_embeddings: | |
embedding_param_names = [ | |
f"{name}.weight" for name, module_type in self.named_modules() if isinstance(module_type, nn.Embedding) | |
] | |
total_parameters = [ | |
parameter for name, parameter in self.named_parameters() if name not in embedding_param_names | |
] | |
else: | |
total_parameters = list(self.parameters()) | |
total_numel = [] | |
is_loaded_in_4bit = getattr(self, "is_loaded_in_4bit", False) | |
if is_loaded_in_4bit: | |
if is_bitsandbytes_available(): | |
import bitsandbytes as bnb | |
else: | |
raise ValueError( | |
"bitsandbytes is not installed but it seems that the model has been loaded in 4bit precision, something went wrong" | |
" make sure to install bitsandbytes with `pip install bitsandbytes`. You also need a GPU. " | |
) | |
for param in total_parameters: | |
if param.requires_grad or not only_trainable: | |
# For 4bit models, we need to multiply the number of parameters by 2 as half of the parameters are | |
# used for the 4bit quantization (uint8 tensors are stored) | |
if is_loaded_in_4bit and isinstance(param, bnb.nn.Params4bit): | |
if hasattr(param, "element_size"): | |
num_bytes = param.element_size() | |
elif hasattr(param, "quant_storage"): | |
num_bytes = param.quant_storage.itemsize | |
else: | |
num_bytes = 1 | |
total_numel.append(param.numel() * 2 * num_bytes) | |
else: | |
total_numel.append(param.numel()) | |
return sum(total_numel) | |
def estimate_tokens(self, input_dict: Dict[str, Union[torch.Tensor, Any]]) -> int: | |
""" | |
Helper function to estimate the total number of tokens from the model inputs. | |
Args: | |
inputs (`dict`): The model inputs. | |
Returns: | |
`int`: The total number of tokens. | |
""" | |
if not hasattr(self, "warnings_issued"): | |
self.warnings_issued = {} | |
if self.main_input_name in input_dict: | |
return input_dict[self.main_input_name].numel() | |
elif "estimate_tokens" not in self.warnings_issued: | |
logger.warning( | |
"Could not estimate the number of tokens of the input, floating-point operations will not be computed" | |
) | |
self.warnings_issued["estimate_tokens"] = True | |
return 0 | |
def floating_point_ops( | |
self, input_dict: Dict[str, Union[torch.Tensor, Any]], exclude_embeddings: bool = True | |
) -> int: | |
""" | |
Get number of (optionally, non-embeddings) floating-point operations for the forward and backward passes of a | |
batch with this transformer model. Default approximation neglects the quadratic dependency on the number of | |
tokens (valid if `12 * d_model << sequence_length`) as laid out in [this | |
paper](https://arxiv.org/pdf/2001.08361.pdf) section 2.1. Should be overridden for transformers with parameter | |
re-use e.g. Albert or Universal Transformers, or if doing long-range modeling with very high sequence lengths. | |
Args: | |
batch_size (`int`): | |
The batch size for the forward pass. | |
sequence_length (`int`): | |
The number of tokens in each line of the batch. | |
exclude_embeddings (`bool`, *optional*, defaults to `True`): | |
Whether or not to count embedding and softmax operations. | |
Returns: | |
`int`: The number of floating-point operations. | |
""" | |
return 6 * self.estimate_tokens(input_dict) * self.num_parameters(exclude_embeddings=exclude_embeddings) | |
class PreTrainedModel(nn.Module, ModuleUtilsMixin, GenerationMixin, PushToHubMixin, PeftAdapterMixin): | |
r""" | |
Base class for all models. | |
[`PreTrainedModel`] takes care of storing the configuration of the models and handles methods for loading, | |
downloading and saving models as well as a few methods common to all models to: | |
- resize the input embeddings, | |
- prune heads in the self-attention heads. | |
Class attributes (overridden by derived classes): | |
- **config_class** ([`PretrainedConfig`]) -- A subclass of [`PretrainedConfig`] to use as configuration class | |
for this model architecture. | |
- **load_tf_weights** (`Callable`) -- A python *method* for loading a TensorFlow checkpoint in a PyTorch model, | |
taking as arguments: | |
- **model** ([`PreTrainedModel`]) -- An instance of the model on which to load the TensorFlow checkpoint. | |
- **config** ([`PreTrainedConfig`]) -- An instance of the configuration associated to the model. | |
- **path** (`str`) -- A path to the TensorFlow checkpoint. | |
- **base_model_prefix** (`str`) -- A string indicating the attribute associated to the base model in derived | |
classes of the same architecture adding modules on top of the base model. | |
- **is_parallelizable** (`bool`) -- A flag indicating whether this model supports model parallelization. | |
- **main_input_name** (`str`) -- The name of the principal input to the model (often `input_ids` for NLP | |
models, `pixel_values` for vision models and `input_values` for speech models). | |
""" | |
config_class = None | |
base_model_prefix = "" | |
main_input_name = "input_ids" | |
model_tags = None | |
_auto_class = None | |
_no_split_modules = None | |
_skip_keys_device_placement = None | |
_keep_in_fp32_modules = None | |
# a list of `re` patterns of `state_dict` keys that should be removed from the list of missing | |
# keys we find (keys inside the model but not in the checkpoint) and avoid unnecessary warnings. | |
_keys_to_ignore_on_load_missing = None | |
# a list of `re` patterns of `state_dict` keys that should be removed from the list of | |
# unexpected keys we find (keys inside the checkpoint but not the model) and avoid unnecessary | |
# warnings. | |
_keys_to_ignore_on_load_unexpected = None | |
# a list of `state_dict` keys to ignore when saving the model (useful for keys that aren't | |
# trained, but which are either deterministic or tied variables) | |
_keys_to_ignore_on_save = None | |
# a list of `state_dict` keys that are potentially tied to another key in the state_dict. | |
_tied_weights_keys = None | |
is_parallelizable = False | |
supports_gradient_checkpointing = False | |
# Flash Attention 2 support | |
_supports_flash_attn_2 = False | |
# SDPA support | |
_supports_sdpa = False | |
# Has support for a `Cache` instance as `past_key_values` | |
_supports_cache_class = False | |
def dummy_inputs(self) -> Dict[str, torch.Tensor]: | |
""" | |
`Dict[str, torch.Tensor]`: Dummy inputs to do a forward pass in the network. | |
""" | |
return {"input_ids": torch.tensor(DUMMY_INPUTS)} | |
def framework(self) -> str: | |
""" | |
:str: Identifies that this is a PyTorch model. | |
""" | |
return "pt" | |
def __init__(self, config: PretrainedConfig, *inputs, **kwargs): | |
super().__init__() | |
if not isinstance(config, PretrainedConfig): | |
raise ValueError( | |
f"Parameter config in `{self.__class__.__name__}(config)` should be an instance of class " | |
"`PretrainedConfig`. To create a model from a pretrained model use " | |
f"`model = {self.__class__.__name__}.from_pretrained(PRETRAINED_MODEL_NAME)`" | |
) | |
# Save config and origin of the pretrained weights if given in model | |
config = self._autoset_attn_implementation( | |
config, torch_dtype=torch.get_default_dtype(), check_device_map=False | |
) | |
self.config = config | |
self.name_or_path = config.name_or_path | |
self.warnings_issued = {} | |
self.generation_config = GenerationConfig.from_model_config(config) if self.can_generate() else None | |
# Overwrite the class attribute to make it an instance attribute, so models like | |
# `InstructBlipForConditionalGeneration` can dynamically update it without modifying the class attribute | |
# when a different component (e.g. language_model) is used. | |
self._keep_in_fp32_modules = copy.copy(self.__class__._keep_in_fp32_modules) | |
def post_init(self): | |
""" | |
A method executed at the end of each Transformer model initialization, to execute code that needs the model's | |
modules properly initialized (such as weight initialization). | |
""" | |
self.init_weights() | |
self._backward_compatibility_gradient_checkpointing() | |
def _backward_compatibility_gradient_checkpointing(self): | |
if self.supports_gradient_checkpointing and getattr(self.config, "gradient_checkpointing", False): | |
self.gradient_checkpointing_enable() | |
# Remove the attribute now that is has been consumed, so it's no saved in the config. | |
delattr(self.config, "gradient_checkpointing") | |
def add_model_tags(self, tags: Union[List[str], str]) -> None: | |
r""" | |
Add custom tags into the model that gets pushed to the Hugging Face Hub. Will | |
not overwrite existing tags in the model. | |
Args: | |
tags (`Union[List[str], str]`): | |
The desired tags to inject in the model | |
Examples: | |
```python | |
from transformers import AutoModel | |
model = AutoModel.from_pretrained("google-bert/bert-base-cased") | |
model.add_model_tags(["custom", "custom-bert"]) | |
# Push the model to your namespace with the name "my-custom-bert". | |
model.push_to_hub("my-custom-bert") | |
``` | |
""" | |
if isinstance(tags, str): | |
tags = [tags] | |
if self.model_tags is None: | |
self.model_tags = [] | |
for tag in tags: | |
if tag not in self.model_tags: | |
self.model_tags.append(tag) | |
def _from_config(cls, config, **kwargs): | |
""" | |
All context managers that the model should be initialized under go here. | |
Args: | |
torch_dtype (`torch.dtype`, *optional*): | |
Override the default `torch.dtype` and load the model under this dtype. | |
""" | |
torch_dtype = kwargs.pop("torch_dtype", None) | |
use_flash_attention_2 = kwargs.pop("use_flash_attention_2", False) | |
# override default dtype if needed | |
dtype_orig = None | |
if torch_dtype is not None: | |
dtype_orig = cls._set_default_torch_dtype(torch_dtype) | |
config = copy.deepcopy(config) # We do not want to modify the config inplace in _from_config. | |
config._attn_implementation = kwargs.pop("attn_implementation", None) | |
config = cls._autoset_attn_implementation( | |
config, | |
use_flash_attention_2=use_flash_attention_2, | |
check_device_map=False, | |
torch_dtype=torch_dtype, | |
) | |
if is_deepspeed_zero3_enabled(): | |
import deepspeed | |
logger.info("Detected DeepSpeed ZeRO-3: activating zero.init() for this model") | |
# this immediately partitions the model across all gpus, to avoid the overhead in time | |
# and memory copying it on CPU or each GPU first | |
with deepspeed.zero.Init(config_dict_or_path=deepspeed_config()): | |
model = cls(config, **kwargs) | |
else: | |
model = cls(config, **kwargs) | |
# restore default dtype if it was modified | |
if dtype_orig is not None: | |
torch.set_default_dtype(dtype_orig) | |
return model | |
def _autoset_attn_implementation( | |
cls, | |
config, | |
use_flash_attention_2: bool = False, | |
torch_dtype: Optional[torch.dtype] = None, | |
device_map: Optional[Union[str, Dict[str, int]]] = None, | |
check_device_map: bool = True, | |
): | |
""" | |
Automatically checks and dispatches to a default attention implementation. In order of priority: | |
1. An implementation specified in `config._attn_implementation` (due for example to the argument attn_implementation="sdpa" in from_pretrained). | |
2. DEPRECATED: if use_flash_attention_2 is set to `True` and `flash_attn` is available, flash attention. (`LlamaFlashAttention` for example) | |
3. SDPA implementation, if available and supported by the model type. (`LlamaSdpaAttention` for example) | |
4. The default model's implementation otherwise (`LlamaAttention` for example) . | |
""" | |
# Here we use config._attn_implementation_internal to check whether the attention implementation was explicitely set by the user. | |
# The property `PretrainedConfig._attn_implementation` is never `None`, for backward compatibility (always fall back on "eager"). | |
# The `hasattr` here is used as some Transformers tests for some reason do not call PretrainedConfig __init__ (e.g. test_no_super_init_config_and_model) | |
requested_attn_implementation = None | |
if hasattr(config, "_attn_implementation_internal") and config._attn_implementation_internal is not None: | |
if config._attn_implementation != "flash_attention_2" and use_flash_attention_2: | |
raise ValueError( | |
f'Both attn_implementation="{config._attn_implementation}" and `use_flash_attention_2=True` were used when loading the model, which are not compatible.' | |
' We recommend to just use `attn_implementation="flash_attention_2"` when loading the model.' | |
) | |
if config._attn_implementation not in ["eager", "sdpa", "flash_attention_2"]: | |
message = f'Specified `attn_implementation="{config._attn_implementation}"` is not supported. The only possible arguments are `attn_implementation="eager"` (manual attention implementation)' | |
if cls._supports_flash_attn_2: | |
message += ', `"attn_implementation=flash_attention_2"` (implementation using flash attention 2)' | |
if cls._supports_sdpa: | |
message += ', `"attn_implementation=sdpa"` (implementation using torch.nn.functional.scaled_dot_product_attention)' | |
raise ValueError(message + ".") | |
# If a config is passed with a preset attn_implementation, we skip the automatic dispatch and use the user-provided config, with hard checks that the requested attention implementation is available. | |
requested_attn_implementation = config._attn_implementation_internal | |
if use_flash_attention_2: | |
logger.warning_once( | |
'The model was loaded with use_flash_attention_2=True, which is deprecated and may be removed in a future release. Please use `attn_implementation="flash_attention_2"` instead.' | |
) | |
config._attn_implementation = "flash_attention_2" | |
if config._attn_implementation == "flash_attention_2": | |
cls._check_and_enable_flash_attn_2( | |
config, | |
torch_dtype=torch_dtype, | |
device_map=device_map, | |
hard_check_only=False, | |
check_device_map=check_device_map, | |
) | |
elif requested_attn_implementation in [None, "sdpa"] and not is_torch_xla_available(): | |
# use_flash_attention_2 takes priority over SDPA, hence SDPA treated in this elif. | |
config = cls._check_and_enable_sdpa( | |
config, | |
hard_check_only=False if requested_attn_implementation is None else True, | |
) | |
else: | |
config._attn_implementation = "eager" | |
return config | |
def _set_default_torch_dtype(cls, dtype: torch.dtype) -> torch.dtype: | |
""" | |
Change the default dtype and return the previous one. This is needed when wanting to instantiate the model | |
under specific dtype. | |
Args: | |
dtype (`torch.dtype`): | |
a floating dtype to set to. | |
Returns: | |
`torch.dtype`: the original `dtype` that can be used to restore `torch.set_default_dtype(dtype)` if it was | |
modified. If it wasn't, returns `None`. | |
Note `set_default_dtype` currently only works with floating-point types and asserts if for example, | |
`torch.int64` is passed. So if a non-float `dtype` is passed this functions will throw an exception. | |
""" | |
if not dtype.is_floating_point: | |
raise ValueError( | |
f"Can't instantiate {cls.__name__} model under dtype={dtype} since it is not a floating point dtype" | |
) | |
logger.info(f"Instantiating {cls.__name__} model under default dtype {dtype}.") | |
dtype_orig = torch.get_default_dtype() | |
torch.set_default_dtype(dtype) | |
return dtype_orig | |
def base_model(self) -> nn.Module: | |
""" | |
`torch.nn.Module`: The main body of the model. | |
""" | |
return getattr(self, self.base_model_prefix, self) | |
def can_generate(cls) -> bool: | |
""" | |
Returns whether this model can generate sequences with `.generate()`. | |
Returns: | |
`bool`: Whether this model can generate sequences with `.generate()`. | |
""" | |
# Detects whether `prepare_inputs_for_generation` has been overwritten, which is a requirement for generation. | |
# Alternativelly, the model can also have a custom `generate` function. | |
if "GenerationMixin" in str(cls.prepare_inputs_for_generation) and "GenerationMixin" in str(cls.generate): | |
return False | |
return True | |
def _check_and_enable_flash_attn_2( | |
cls, | |
config, | |
torch_dtype: Optional[torch.dtype] = None, | |
device_map: Optional[Union[str, Dict[str, int]]] = None, | |
check_device_map: bool = True, | |
hard_check_only: bool = False, | |
) -> PretrainedConfig: | |
""" | |
Checks the availability of Flash Attention 2 and compatibility with the current model. | |
If all checks pass and `hard_check_only` is False, the method will set the config attribute `attn_implementation` to "flash_attention_2" so that the model can initialize the correct attention module. | |
""" | |
if not cls._supports_flash_attn_2: | |
raise ValueError( | |
f"{cls.__name__} does not support Flash Attention 2.0 yet. Please request to add support where" | |
f" the model is hosted, on its model hub page: https://huggingface.co/{config._name_or_path}/discussions/new" | |
" or in the Transformers GitHub repo: https://github.com/huggingface/transformers/issues/new" | |
) | |
if not is_flash_attn_2_available(): | |
preface = "FlashAttention2 has been toggled on, but it cannot be used due to the following error:" | |
install_message = "Please refer to the documentation of https://huggingface.co/docs/transformers/perf_infer_gpu_one#flashattention-2 to install Flash Attention 2." | |
if importlib.util.find_spec("flash_attn") is None: | |
raise ImportError(f"{preface} the package flash_attn seems to be not installed. {install_message}") | |
flash_attention_version = version.parse(importlib.metadata.version("flash_attn")) | |
if torch.version.cuda: | |
if flash_attention_version < version.parse("2.1.0"): | |
raise ImportError( | |
f"{preface} you need flash_attn package version to be greater or equal than 2.1.0. Detected version {flash_attention_version}. {install_message}" | |
) | |
else: | |
raise ImportError(f"{preface} Flash Attention 2 is not available. {install_message}") | |
elif torch.version.hip: | |
if flash_attention_version < version.parse("2.0.4"): | |
raise ImportError( | |
f"{preface} you need flash_attn package version to be greater or equal than 2.0.4. Make sure to have that version installed - detected version {flash_attention_version}. {install_message}" | |
) | |
else: | |
raise ImportError(f"{preface} Flash Attention 2 is not available. {install_message}") | |
_is_bettertransformer = getattr(cls, "use_bettertransformer", False) | |
if _is_bettertransformer: | |
raise ValueError( | |
"Flash Attention 2 and BetterTransformer API are not compatible. Please make sure to disable BetterTransformers by doing model.reverse_bettertransformer()" | |
) | |
if torch_dtype is None: | |
logger.warning_once( | |
"You are attempting to use Flash Attention 2.0 without specifying a torch dtype. This might lead to unexpected behaviour" | |
) | |
elif torch_dtype is not None and torch_dtype not in [torch.float16, torch.bfloat16]: | |
logger.warning_once( | |
"Flash Attention 2.0 only supports torch.float16 and torch.bfloat16 dtypes, but" | |
f" the current dype in {cls.__name__} is {torch_dtype}. You should run training or inference using Automatic Mixed-Precision via the `with torch.autocast(device_type='torch_device'):` decorator," | |
' or load the model with the `torch_dtype` argument. Example: `model = AutoModel.from_pretrained("openai/whisper-tiny", attn_implementation="flash_attention_2", torch_dtype=torch.float16)`' | |
) | |
# The check `torch.empty(0).device.type != "cuda"` is needed as the model may be initialized after `torch.set_default_device` has been called, | |
# or the model may be initialized under the context manager `with torch.device("cuda"):`. | |
if check_device_map and device_map is None and torch.empty(0).device.type != "cuda": | |
if torch.cuda.is_available(): | |
logger.warning_once( | |
"You are attempting to use Flash Attention 2.0 with a model not initialized on GPU. Make sure to move the model to GPU" | |
" after initializing it on CPU with `model.to('cuda')`." | |
) | |
else: | |
raise ValueError( | |
"You are attempting to use Flash Attention 2.0 with a model not initialized on GPU and with no GPU available. " | |
"This is not supported yet. Please make sure to have access to a GPU and either initialise the model on a GPU by passing a device_map " | |
"or initialising the model on CPU and then moving it to GPU." | |
) | |
elif ( | |
check_device_map | |
and device_map is not None | |
and isinstance(device_map, dict) | |
and ("cpu" in device_map.values() or "disk" in device_map.values()) | |
): | |
raise ValueError( | |
"You are attempting to use Flash Attention 2.0 with a model dispatched on CPU or disk. This is not supported. Please make sure to " | |
"initialise the model on a GPU by passing a device_map that contains only GPU devices as keys." | |
) | |
if not hard_check_only: | |
config._attn_implementation = "flash_attention_2" | |
return config | |
def _check_and_enable_sdpa(cls, config, hard_check_only: bool = False) -> PretrainedConfig: | |
""" | |
Checks the availability of SDPA for a given model. | |
If all checks pass and `hard_check_only` is False, the method will set the config attribute `_attn_implementation` to "flash_attention_2" so that the model can initialize the correct attention module. | |
""" | |
if hard_check_only: | |
if not cls._supports_sdpa: | |
raise ValueError( | |
f"{cls.__name__} does not support an attention implementation through torch.nn.functional.scaled_dot_product_attention yet." | |
" Please request the support for this architecture: https://github.com/huggingface/transformers/issues/28005. If you believe" | |
' this error is a bug, please open an issue in Transformers GitHub repository and load your model with the argument `attn_implementation="eager"` meanwhile. Example: `model = AutoModel.from_pretrained("openai/whisper-tiny", attn_implementation="eager")`' | |
) | |
if not is_torch_sdpa_available(): | |
raise ImportError( | |
"PyTorch SDPA requirements in Transformers are not met. Please install torch>=2.1.1." | |
) | |
if not is_torch_sdpa_available() or not cls._supports_sdpa: | |
return config | |
_is_bettertransformer = getattr(cls, "use_bettertransformer", False) | |
if _is_bettertransformer: | |
return config | |
if not hard_check_only: | |
config._attn_implementation = "sdpa" | |
return config | |
def enable_input_require_grads(self): | |
""" | |
Enables the gradients for the input embeddings. This is useful for fine-tuning adapter weights while keeping | |
the model weights fixed. | |
""" | |
def make_inputs_require_grads(module, input, output): | |
output.requires_grad_(True) | |
self._require_grads_hook = self.get_input_embeddings().register_forward_hook(make_inputs_require_grads) | |
def disable_input_require_grads(self): | |
""" | |
Removes the `_require_grads_hook`. | |
""" | |
self._require_grads_hook.remove() | |
def get_input_embeddings(self) -> nn.Module: | |
""" | |
Returns the model's input embeddings. | |
Returns: | |
`nn.Module`: A torch module mapping vocabulary to hidden states. | |
""" | |
base_model = getattr(self, self.base_model_prefix, self) | |
if base_model is not self: | |
return base_model.get_input_embeddings() | |
else: | |
raise NotImplementedError | |
def set_input_embeddings(self, value: nn.Module): | |
""" | |
Set model's input embeddings. | |
Args: | |
value (`nn.Module`): A module mapping vocabulary to hidden states. | |
""" | |
base_model = getattr(self, self.base_model_prefix, self) | |
if base_model is not self: | |
base_model.set_input_embeddings(value) | |
else: | |
raise NotImplementedError | |
def get_output_embeddings(self) -> nn.Module: | |
""" | |
Returns the model's output embeddings. | |
Returns: | |
`nn.Module`: A torch module mapping hidden states to vocabulary. | |
""" | |
return None # Overwrite for models with output embeddings | |
def _init_weights(self, module): | |
""" | |
Initialize the weights. This method should be overridden by derived class and is | |
the only initialization method that will be called when loading a checkpoint | |
using `from_pretrained`. Any attempt to initialize outside of this function | |
will be useless as the torch.nn.init function are all replaced with skip. | |
""" | |
pass | |
def _initialize_weights(self, module): | |
""" | |
Initialize the weights if they are not already initialized. | |
""" | |
if getattr(module, "_is_hf_initialized", False): | |
return | |
self._init_weights(module) | |
module._is_hf_initialized = True | |
def tie_weights(self): | |
""" | |
Tie the weights between the input embeddings and the output embeddings. | |
If the `torchscript` flag is set in the configuration, can't handle parameter sharing so we are cloning the | |
weights instead. | |
""" | |
if getattr(self.config, "tie_word_embeddings", True): | |
output_embeddings = self.get_output_embeddings() | |
if output_embeddings is not None: | |
self._tie_or_clone_weights(output_embeddings, self.get_input_embeddings()) | |
if getattr(self.config, "is_encoder_decoder", False) and getattr(self.config, "tie_encoder_decoder", False): | |
if hasattr(self, self.base_model_prefix): | |
self = getattr(self, self.base_model_prefix) | |
tied_weights = self._tie_encoder_decoder_weights( | |
self.encoder, self.decoder, self.base_model_prefix, "encoder" | |
) | |
# Setting a dynamic variable instead of `_tied_weights_keys` because it's a class | |
# attributed not an instance member, therefore modifying it will modify the entire class | |
# Leading to issues on subsequent calls by different tests or subsequent calls. | |
self._dynamic_tied_weights_keys = tied_weights | |
for module in self.modules(): | |
if hasattr(module, "_tie_weights"): | |
module._tie_weights() | |
def _tie_encoder_decoder_weights( | |
encoder: nn.Module, decoder: nn.Module, base_model_prefix: str, base_encoder_name: str | |
): | |
uninitialized_encoder_weights: List[str] = [] | |
tied_weights: List[str] = [] | |
if decoder.__class__ != encoder.__class__: | |
logger.info( | |
f"{decoder.__class__} and {encoder.__class__} are not equal. In this case make sure that all encoder" | |
" weights are correctly initialized." | |
) | |
def tie_encoder_to_decoder_recursively( | |
decoder_pointer: nn.Module, | |
encoder_pointer: nn.Module, | |
module_name: str, | |
base_encoder_name: str, | |
uninitialized_encoder_weights: List[str], | |
depth=0, | |
total_decoder_name="", | |
total_encoder_name="", | |
): | |
assert isinstance(decoder_pointer, nn.Module) and isinstance( | |
encoder_pointer, nn.Module | |
), f"{decoder_pointer} and {encoder_pointer} have to be of type nn.Module" | |
if hasattr(decoder_pointer, "weight"): | |
assert hasattr(encoder_pointer, "weight") | |
encoder_pointer.weight = decoder_pointer.weight | |
tied_weights.append(f"{base_encoder_name}{total_encoder_name}.weight") | |
if hasattr(decoder_pointer, "bias"): | |
assert hasattr(encoder_pointer, "bias") | |
tied_weights.append(f"{base_encoder_name}{total_encoder_name}.bias") | |
encoder_pointer.bias = decoder_pointer.bias | |
return | |
encoder_modules = encoder_pointer._modules | |
decoder_modules = decoder_pointer._modules | |
if len(decoder_modules) > 0: | |
assert ( | |
len(encoder_modules) > 0 | |
), f"Encoder module {encoder_pointer} does not match decoder module {decoder_pointer}" | |
all_encoder_weights = {module_name + "/" + sub_name for sub_name in encoder_modules.keys()} | |
encoder_layer_pos = 0 | |
for name, module in decoder_modules.items(): | |
if name.isdigit(): | |
encoder_name = str(int(name) + encoder_layer_pos) | |
decoder_name = name | |
if not isinstance(decoder_modules[decoder_name], type(encoder_modules[encoder_name])) and len( | |
encoder_modules | |
) != len(decoder_modules): | |
# this can happen if the name corresponds to the position in a list module list of layers | |
# in this case the decoder has added a cross-attention that the encoder does not have | |
# thus skip this step and subtract one layer pos from encoder | |
encoder_layer_pos -= 1 | |
continue | |
elif name not in encoder_modules: | |
continue | |
elif depth > 500: | |
raise ValueError( | |
"Max depth of recursive function `tie_encoder_to_decoder` reached. It seems that there is" | |
" a circular dependency between two or more `nn.Modules` of your model." | |
) | |
else: | |
decoder_name = encoder_name = name | |
tie_encoder_to_decoder_recursively( | |
decoder_modules[decoder_name], | |
encoder_modules[encoder_name], | |
module_name + "/" + name, | |
base_encoder_name, | |
uninitialized_encoder_weights, | |
depth=depth + 1, | |
total_encoder_name=f"{total_encoder_name}.{encoder_name}", | |
total_decoder_name=f"{total_decoder_name}.{decoder_name}", | |
) | |
all_encoder_weights.remove(module_name + "/" + encoder_name) | |
uninitialized_encoder_weights += list(all_encoder_weights) | |
# tie weights recursively | |
tie_encoder_to_decoder_recursively( | |
decoder, encoder, base_model_prefix, base_encoder_name, uninitialized_encoder_weights | |
) | |
if len(uninitialized_encoder_weights) > 0: | |
logger.warning( | |
f"The following encoder weights were not tied to the decoder {uninitialized_encoder_weights}" | |
) | |
return tied_weights | |
def _tie_or_clone_weights(self, output_embeddings, input_embeddings): | |
"""Tie or clone module weights depending of whether we are using TorchScript or not""" | |
if self.config.torchscript: | |
output_embeddings.weight = nn.Parameter(input_embeddings.weight.clone()) | |
else: | |
output_embeddings.weight = input_embeddings.weight | |
if getattr(output_embeddings, "bias", None) is not None: | |
output_embeddings.bias.data = nn.functional.pad( | |
output_embeddings.bias.data, | |
( | |
0, | |
output_embeddings.weight.shape[0] - output_embeddings.bias.shape[0], | |
), | |
"constant", | |
0, | |
) | |
if hasattr(output_embeddings, "out_features") and hasattr(input_embeddings, "num_embeddings"): | |
output_embeddings.out_features = input_embeddings.num_embeddings | |
def _get_no_split_modules(self, device_map: str): | |
""" | |
Get the modules of the model that should not be spit when using device_map. We iterate through the modules to | |
get the underlying `_no_split_modules`. | |
Args: | |
device_map (`str`): | |
The device map value. Options are ["auto", "balanced", "balanced_low_0", "sequential"] | |
Returns: | |
`List[str]`: List of modules that should not be split | |
""" | |
_no_split_modules = set() | |
modules_to_check = [self] | |
while len(modules_to_check) > 0: | |
module = modules_to_check.pop(-1) | |
# if the module does not appear in _no_split_modules, we also check the children | |
if module.__class__.__name__ not in _no_split_modules: | |
if isinstance(module, PreTrainedModel): | |
if module._no_split_modules is None: | |
raise ValueError( | |
f"{module.__class__.__name__} does not support `device_map='{device_map}'`. To implement support, the model " | |
"class needs to implement the `_no_split_modules` attribute." | |
) | |
else: | |
_no_split_modules = _no_split_modules | set(module._no_split_modules) | |
modules_to_check += list(module.children()) | |
return list(_no_split_modules) | |
def resize_token_embeddings( | |
self, new_num_tokens: Optional[int] = None, pad_to_multiple_of: Optional[int] = None | |
) -> nn.Embedding: | |
""" | |
Resizes input token embeddings matrix of the model if `new_num_tokens != config.vocab_size`. | |
Takes care of tying weights embeddings afterwards if the model class has a `tie_weights()` method. | |
Arguments: | |
new_num_tokens (`int`, *optional*): | |
The new number of tokens in the embedding matrix. Increasing the size will add newly initialized | |
vectors at the end. Reducing the size will remove vectors from the end. If not provided or `None`, just | |
returns a pointer to the input tokens `torch.nn.Embedding` module of the model without doing anything. | |
pad_to_multiple_of (`int`, *optional*): | |
If set will pad the embedding matrix to a multiple of the provided value.If `new_num_tokens` is set to | |
`None` will just pad the embedding to a multiple of `pad_to_multiple_of`. | |
This is especially useful to enable the use of Tensor Cores on NVIDIA hardware with compute capability | |
`>= 7.5` (Volta), or on TPUs which benefit from having sequence lengths be a multiple of 128. For more | |
details about this, or help on choosing the correct value for resizing, refer to this guide: | |
https://docs.nvidia.com/deeplearning/performance/dl-performance-matrix-multiplication/index.html#requirements-tc | |
Return: | |
`torch.nn.Embedding`: Pointer to the input tokens Embeddings Module of the model. | |
""" | |
model_embeds = self._resize_token_embeddings(new_num_tokens, pad_to_multiple_of) | |
if new_num_tokens is None and pad_to_multiple_of is None: | |
return model_embeds | |
# Update base model and current model config | |
self.config.vocab_size = model_embeds.weight.shape[0] | |
self.vocab_size = model_embeds.weight.shape[0] | |
# Tie weights again if needed | |
self.tie_weights() | |
return model_embeds | |
def _resize_token_embeddings(self, new_num_tokens, pad_to_multiple_of=None): | |
old_embeddings = self.get_input_embeddings() | |
new_embeddings = self._get_resized_embeddings(old_embeddings, new_num_tokens, pad_to_multiple_of) | |
if hasattr(old_embeddings, "_hf_hook"): | |
hook = old_embeddings._hf_hook | |
add_hook_to_module(new_embeddings, hook) | |
old_embeddings_requires_grad = old_embeddings.weight.requires_grad | |
new_embeddings.requires_grad_(old_embeddings_requires_grad) | |
self.set_input_embeddings(new_embeddings) | |
is_quantized = hasattr(self, "hf_quantizer") and self.hf_quantizer is not None | |
# Update new_num_tokens with the actual size of new_embeddings | |
if pad_to_multiple_of is not None: | |
if is_deepspeed_zero3_enabled() and not is_quantized: | |
import deepspeed | |
with deepspeed.zero.GatheredParameters(new_embeddings.weight, modifier_rank=None): | |
new_num_tokens = new_embeddings.weight.shape[0] | |
else: | |
new_num_tokens = new_embeddings.weight.shape[0] | |
# if word embeddings are not tied, make sure that lm head is resized as well | |
if self.get_output_embeddings() is not None and not self.config.tie_word_embeddings: | |
old_lm_head = self.get_output_embeddings() | |
if isinstance(old_lm_head, torch.nn.Embedding): | |
new_lm_head = self._get_resized_embeddings(old_lm_head, new_num_tokens) | |
else: | |
new_lm_head = self._get_resized_lm_head(old_lm_head, new_num_tokens) | |
if hasattr(old_lm_head, "_hf_hook"): | |
hook = old_lm_head._hf_hook | |
add_hook_to_module(new_lm_head, hook) | |
old_lm_head_requires_grad = old_lm_head.weight.requires_grad | |
new_lm_head.requires_grad_(old_lm_head_requires_grad) | |
self.set_output_embeddings(new_lm_head) | |
return self.get_input_embeddings() | |
def _get_resized_embeddings( | |
self, | |
old_embeddings: nn.Embedding, | |
new_num_tokens: Optional[int] = None, | |
pad_to_multiple_of: Optional[int] = None, | |
) -> nn.Embedding: | |
""" | |
Build a resized Embedding Module from a provided token Embedding Module. Increasing the size will add newly | |
initialized vectors at the end. Reducing the size will remove vectors from the end | |
Args: | |
old_embeddings (`torch.nn.Embedding`): | |
Old embeddings to be resized. | |
new_num_tokens (`int`, *optional*): | |
New number of tokens in the embedding matrix. | |
Increasing the size will add newly initialized vectors at the end. Reducing the size will remove | |
vectors from the end. If not provided or `None`, just returns a pointer to the input tokens | |
`torch.nn.Embedding` module of the model without doing anything. | |
pad_to_multiple_of (`int`, *optional*): | |
If set will pad the embedding matrix to a multiple of the provided value. If `new_num_tokens` is set to | |
`None` will just pad the embedding to a multiple of `pad_to_multiple_of`. | |
This is especially useful to enable the use of Tensor Cores on NVIDIA hardware with compute capability | |
`>= 7.5` (Volta), or on TPUs which benefit from having sequence lengths be a multiple of 128. For more | |
details about this, or help on choosing the correct value for resizing, refer to this guide: | |
https://docs.nvidia.com/deeplearning/performance/dl-performance-matrix-multiplication/index.html#requirements-tc | |
Return: | |
`torch.nn.Embedding`: Pointer to the resized Embedding Module or the old Embedding Module if | |
`new_num_tokens` is `None` | |
""" | |
if pad_to_multiple_of is not None: | |
if not isinstance(pad_to_multiple_of, int): | |
raise ValueError( | |
f"Asking to pad the embedding matrix to a multiple of `{pad_to_multiple_of}`, which is not and integer. Please make sure to pass an integer" | |
) | |
if new_num_tokens is None: | |
new_num_tokens = old_embeddings.weight.shape[0] | |
new_num_tokens = ((new_num_tokens + pad_to_multiple_of - 1) // pad_to_multiple_of) * pad_to_multiple_of | |
else: | |
logger.info( | |
"You are resizing the embedding layer without providing a `pad_to_multiple_of` parameter. This means that the new embedding" | |
f" dimension will be {new_num_tokens}. This might induce some performance reduction as *Tensor Cores* will not be available." | |
" For more details about this, or help on choosing the correct value for resizing, refer to this guide:" | |
" https://docs.nvidia.com/deeplearning/performance/dl-performance-matrix-multiplication/index.html#requirements-tc" | |
) | |
if new_num_tokens is None: | |
return old_embeddings | |
is_quantized = hasattr(self, "hf_quantizer") and self.hf_quantizer is not None | |
if is_deepspeed_zero3_enabled() and not is_quantized: | |
import deepspeed | |
with deepspeed.zero.GatheredParameters(old_embeddings.weight, modifier_rank=None): | |
old_num_tokens, old_embedding_dim = old_embeddings.weight.size() | |
else: | |
old_num_tokens, old_embedding_dim = old_embeddings.weight.size() | |
if old_num_tokens == new_num_tokens and not is_deepspeed_zero3_enabled(): | |
return old_embeddings | |
if not isinstance(old_embeddings, nn.Embedding): | |
raise TypeError( | |
f"Old embeddings are of type {type(old_embeddings)}, which is not an instance of {nn.Embedding}. You" | |
" should either use a different resize function or make sure that `old_embeddings` are an instance of" | |
f" {nn.Embedding}." | |
) | |
# Build new embeddings | |
# When using DeepSpeed ZeRO-3, we shouldn't create new embeddings with DeepSpeed init | |
# because the shape of the new embedding layer is used across various modeling files | |
# as well as to update config vocab size. Shape will be 0 when using DeepSpeed init leading | |
# to errors when training. | |
new_embeddings = nn.Embedding( | |
new_num_tokens, | |
old_embedding_dim, | |
device=old_embeddings.weight.device, | |
dtype=old_embeddings.weight.dtype, | |
) | |
# initialize all new embeddings (in particular added tokens) | |
self._init_weights(new_embeddings) | |
# Copy token embeddings from the previous weights | |
# numbers of tokens to copy | |
n = min(old_num_tokens, new_num_tokens) | |
if is_deepspeed_zero3_enabled() and not is_quantized: | |
import deepspeed | |
params = [old_embeddings.weight, new_embeddings.weight] | |
with deepspeed.zero.GatheredParameters(params, modifier_rank=0): | |
new_embeddings.weight.data[:n, :] = old_embeddings.weight.data[:n, :] | |
else: | |
new_embeddings.weight.data[:n, :] = old_embeddings.weight.data[:n, :] | |
return new_embeddings | |
def _get_resized_lm_head( | |
self, old_lm_head: nn.Linear, new_num_tokens: Optional[int] = None, transposed: Optional[bool] = False | |
) -> nn.Linear: | |
""" | |
Build a resized Linear Module from a provided old Linear Module. Increasing the size will add newly initialized | |
vectors at the end. Reducing the size will remove vectors from the end | |
Args: | |
old_lm_head (`torch.nn.Linear`): | |
Old lm head liner layer to be resized. | |
new_num_tokens (`int`, *optional*): | |
New number of tokens in the linear matrix. | |
Increasing the size will add newly initialized vectors at the end. Reducing the size will remove | |
vectors from the end. If not provided or `None`, just returns a pointer to the input tokens | |
`torch.nn.Linear` module of the model without doing anything. transposed (`bool`, *optional*, defaults | |
to `False`): Whether `old_lm_head` is transposed or not. If True `old_lm_head.size()` is `lm_head_dim, | |
vocab_size` else `vocab_size, lm_head_dim`. | |
Return: | |
`torch.nn.Linear`: Pointer to the resized Linear Module or the old Linear Module if `new_num_tokens` is | |
`None` | |
""" | |
if new_num_tokens is None: | |
return old_lm_head | |
is_quantized = hasattr(self, "hf_quantizer") and self.hf_quantizer is not None | |
if is_deepspeed_zero3_enabled() and not is_quantized: | |
import deepspeed | |
with deepspeed.zero.GatheredParameters(old_lm_head.weight, modifier_rank=None): | |
old_num_tokens, old_lm_head_dim = ( | |
old_lm_head.weight.size() if not transposed else old_lm_head.weight.t().size() | |
) | |
else: | |
old_num_tokens, old_lm_head_dim = ( | |
old_lm_head.weight.size() if not transposed else old_lm_head.weight.t().size() | |
) | |
if old_num_tokens == new_num_tokens and not is_deepspeed_zero3_enabled(): | |
return old_lm_head | |
if not isinstance(old_lm_head, nn.Linear): | |
raise TypeError( | |
f"Old language model head is of type {type(old_lm_head)}, which is not an instance of {nn.Linear}. You" | |
" should either use a different resize function or make sure that `old_lm_head` are an instance of" | |
f" {nn.Linear}." | |
) | |
# Build new lm head | |
new_lm_head_shape = (old_lm_head_dim, new_num_tokens) if not transposed else (new_num_tokens, old_lm_head_dim) | |
has_new_lm_head_bias = old_lm_head.bias is not None | |
# When using DeepSpeed ZeRO-3, we shouldn't create new embeddings with DeepSpeed init | |
# because the shape of the new embedding layer is used across various modeling files | |
# as well as to update config vocab size. Shape will be 0 when using DeepSpeed init leading | |
# to errors when training. | |
new_lm_head = nn.Linear( | |
*new_lm_head_shape, | |
bias=has_new_lm_head_bias, | |
device=old_lm_head.weight.device, | |
dtype=old_lm_head.weight.dtype, | |
) | |
# initialize new lm head (in particular added tokens) | |
self._init_weights(new_lm_head) | |
num_tokens_to_copy = min(old_num_tokens, new_num_tokens) | |
if is_deepspeed_zero3_enabled() and not is_quantized: | |
import deepspeed | |
params = [old_lm_head.weight, old_lm_head.bias, new_lm_head.weight, new_lm_head.bias] | |
with deepspeed.zero.GatheredParameters(params, modifier_rank=0): | |
self._copy_lm_head_original_to_resized( | |
new_lm_head, old_lm_head, num_tokens_to_copy, transposed, has_new_lm_head_bias | |
) | |
else: | |
self._copy_lm_head_original_to_resized( | |
new_lm_head, old_lm_head, num_tokens_to_copy, transposed, has_new_lm_head_bias | |
) | |
return new_lm_head | |
def _copy_lm_head_original_to_resized( | |
self, new_lm_head, old_lm_head, num_tokens_to_copy, transposed, has_new_lm_head_bias | |
): | |
# Copy old lm head weights to new lm head | |
if not transposed: | |
new_lm_head.weight.data[:num_tokens_to_copy, :] = old_lm_head.weight.data[:num_tokens_to_copy, :] | |
else: | |
new_lm_head.weight.data[:, :num_tokens_to_copy] = old_lm_head.weight.data[:, :num_tokens_to_copy] | |
# Copy bias weights to new lm head | |
if has_new_lm_head_bias: | |
new_lm_head.bias.data[:num_tokens_to_copy] = old_lm_head.bias.data[:num_tokens_to_copy] | |
def resize_position_embeddings(self, new_num_position_embeddings: int): | |
raise NotImplementedError( | |
f"`resize_position_embeddings` is not implemented for {self.__class__}`. To implement it, you should " | |
f"overwrite this method in the class {self.__class__} in `modeling_{self.__class__.__module__}.py`" | |
) | |
def get_position_embeddings(self) -> Union[nn.Embedding, Tuple[nn.Embedding]]: | |
raise NotImplementedError( | |
f"`get_position_embeddings` is not implemented for {self.__class__}`. To implement it, you should " | |
f"overwrite this method in the class {self.__class__} in `modeling_{self.__class__.__module__}.py`" | |
) | |
def init_weights(self): | |
""" | |
If needed prunes and maybe initializes weights. If using a custom `PreTrainedModel`, you need to implement any | |
initialization logic in `_init_weights`. | |
""" | |
# Prune heads if needed | |
if self.config.pruned_heads: | |
self.prune_heads(self.config.pruned_heads) | |
if _init_weights: | |
# Initialize weights | |
self.apply(self._initialize_weights) | |
# Tie weights should be skipped when not initializing all weights | |
# since from_pretrained(...) calls tie weights anyways | |
self.tie_weights() | |
def prune_heads(self, heads_to_prune: Dict[int, List[int]]): | |
""" | |
Prunes heads of the base model. | |
Arguments: | |
heads_to_prune (`Dict[int, List[int]]`): | |
Dictionary with keys being selected layer indices (`int`) and associated values being the list of heads | |
to prune in said layer (list of `int`). For instance {1: [0, 2], 2: [2, 3]} will prune heads 0 and 2 on | |
layer 1 and heads 2 and 3 on layer 2. | |
""" | |
# save new sets of pruned heads as union of previously stored pruned heads and newly pruned heads | |
for layer, heads in heads_to_prune.items(): | |
union_heads = set(self.config.pruned_heads.get(layer, [])) | set(heads) | |
self.config.pruned_heads[layer] = list(union_heads) # Unfortunately we have to store it as list for JSON | |
self.base_model._prune_heads(heads_to_prune) | |
def gradient_checkpointing_enable(self, gradient_checkpointing_kwargs=None): | |
""" | |
Activates gradient checkpointing for the current model. | |
Note that in other frameworks this feature can be referred to as "activation checkpointing" or "checkpoint | |
activations". | |
We pass the `__call__` method of the modules instead of `forward` because `__call__` attaches all the hooks of | |
the module. https://discuss.pytorch.org/t/any-different-between-model-input-and-model-forward-input/3690/2 | |
Args: | |
gradient_checkpointing_kwargs (dict, *optional*): | |
Additional keyword arguments passed along to the `torch.utils.checkpoint.checkpoint` function. | |
""" | |
if not self.supports_gradient_checkpointing: | |
raise ValueError(f"{self.__class__.__name__} does not support gradient checkpointing.") | |
if gradient_checkpointing_kwargs is None: | |
gradient_checkpointing_kwargs = {"use_reentrant": True} | |
gradient_checkpointing_func = functools.partial(checkpoint, **gradient_checkpointing_kwargs) | |
# For old GC format (transformers < 4.35.0) for models that live on the Hub | |
# we will fall back to the overwritten `_set_gradient_checkpointing` method | |
_is_using_old_format = "value" in inspect.signature(self._set_gradient_checkpointing).parameters | |
if not _is_using_old_format: | |
self._set_gradient_checkpointing(enable=True, gradient_checkpointing_func=gradient_checkpointing_func) | |
else: | |
self.apply(partial(self._set_gradient_checkpointing, value=True)) | |
logger.warning( | |
"You are using an old version of the checkpointing format that is deprecated (We will also silently ignore `gradient_checkpointing_kwargs` in case you passed it)." | |
"Please update to the new format on your modeling file. To use the new format, you need to completely remove the definition of the method `_set_gradient_checkpointing` in your model." | |
) | |
if getattr(self, "_hf_peft_config_loaded", False): | |
# When using PEFT + gradient checkpointing + Trainer we need to make sure the input has requires_grad=True | |
# we do it also on PEFT: https://github.com/huggingface/peft/blob/85013987aa82aa1af3da1236b6902556ce3e483e/src/peft/peft_model.py#L334 | |
# When training with PEFT, only LoRA layers will have requires grad set to True, but the output of frozen layers need to propagate | |
# the gradients to make sure the gradient flows. | |
self.enable_input_require_grads() | |
def _set_gradient_checkpointing(self, enable: bool = True, gradient_checkpointing_func: Callable = checkpoint): | |
is_gradient_checkpointing_set = False | |
# Apply it on the top-level module in case the top-level modules supports it | |
# for example, LongT5Stack inherits from `PreTrainedModel`. | |
if hasattr(self, "gradient_checkpointing"): | |
self._gradient_checkpointing_func = gradient_checkpointing_func | |
self.gradient_checkpointing = enable | |
is_gradient_checkpointing_set = True | |
for module in self.modules(): | |
if hasattr(module, "gradient_checkpointing"): | |
module._gradient_checkpointing_func = gradient_checkpointing_func | |
module.gradient_checkpointing = enable | |
is_gradient_checkpointing_set = True | |
if not is_gradient_checkpointing_set: | |
raise ValueError( | |
f"{self.__class__.__name__} is not compatible with gradient checkpointing. Make sure all the architecture support it by setting a boolean attribute" | |
" `gradient_checkpointing` to modules of the model that uses checkpointing." | |
) | |
def gradient_checkpointing_disable(self): | |
""" | |
Deactivates gradient checkpointing for the current model. | |
Note that in other frameworks this feature can be referred to as "activation checkpointing" or "checkpoint | |
activations". | |
""" | |
if self.supports_gradient_checkpointing: | |
# For old GC format (transformers < 4.35.0) for models that live on the Hub | |
# we will fall back to the overwritten `_set_gradient_checkpointing` methid | |
_is_using_old_format = "value" in inspect.signature(self._set_gradient_checkpointing).parameters | |
if not _is_using_old_format: | |
self._set_gradient_checkpointing(enable=False) | |
else: | |
logger.warning( | |
"You are using an old version of the checkpointing format that is deprecated (We will also silently ignore `gradient_checkpointing_kwargs` in case you passed it)." | |
"Please update to the new format on your modeling file. To use the new format, you need to completely remove the definition of the method `_set_gradient_checkpointing` in your model." | |
) | |
self.apply(partial(self._set_gradient_checkpointing, value=False)) | |
if getattr(self, "_hf_peft_config_loaded", False): | |
self.disable_input_require_grads() | |
def is_gradient_checkpointing(self) -> bool: | |
""" | |
Whether gradient checkpointing is activated for this model or not. | |
Note that in other frameworks this feature can be referred to as "activation checkpointing" or "checkpoint | |
activations". | |
""" | |
return any(hasattr(m, "gradient_checkpointing") and m.gradient_checkpointing for m in self.modules()) | |
def save_pretrained( | |
self, | |
save_directory: Union[str, os.PathLike], | |
is_main_process: bool = True, | |
state_dict: Optional[dict] = None, | |
save_function: Callable = torch.save, | |
push_to_hub: bool = False, | |
max_shard_size: Union[int, str] = "5GB", | |
safe_serialization: bool = True, | |
variant: Optional[str] = None, | |
token: Optional[Union[str, bool]] = None, | |
save_peft_format: bool = True, | |
**kwargs, | |
): | |
""" | |
Save a model and its configuration file to a directory, so that it can be re-loaded using the | |
[`~PreTrainedModel.from_pretrained`] class method. | |
Arguments: | |
save_directory (`str` or `os.PathLike`): | |
Directory to which to save. Will be created if it doesn't exist. | |
is_main_process (`bool`, *optional*, defaults to `True`): | |
Whether the process calling this is the main process or not. Useful when in distributed training like | |
TPUs and need to call this function on all processes. In this case, set `is_main_process=True` only on | |
the main process to avoid race conditions. | |
state_dict (nested dictionary of `torch.Tensor`): | |
The state dictionary of the model to save. Will default to `self.state_dict()`, but can be used to only | |
save parts of the model or if special precautions need to be taken when recovering the state dictionary | |
of a model (like when using model parallelism). | |
save_function (`Callable`): | |
The function to use to save the state dictionary. Useful on distributed training like TPUs when one | |
need to replace `torch.save` by another method. | |
push_to_hub (`bool`, *optional*, defaults to `False`): | |
Whether or not to push your model to the Hugging Face model hub after saving it. You can specify the | |
repository you want to push to with `repo_id` (will default to the name of `save_directory` in your | |
namespace). | |
max_shard_size (`int` or `str`, *optional*, defaults to `"5GB"`): | |
The maximum size for a checkpoint before being sharded. Checkpoints shard will then be each of size | |
lower than this size. If expressed as a string, needs to be digits followed by a unit (like `"5MB"`). | |
We default it to 5GB in order for models to be able to run easily on free-tier google colab instances | |
without CPU OOM issues. | |
<Tip warning={true}> | |
If a single weight of the model is bigger than `max_shard_size`, it will be in its own checkpoint shard | |
which will be bigger than `max_shard_size`. | |
</Tip> | |
safe_serialization (`bool`, *optional*, defaults to `True`): | |
Whether to save the model using `safetensors` or the traditional PyTorch way (that uses `pickle`). | |
variant (`str`, *optional*): | |
If specified, weights are saved in the format pytorch_model.<variant>.bin. | |
token (`str` or `bool`, *optional*): | |
The token to use as HTTP bearer authorization for remote files. If `True`, or not specified, will use | |
the token generated when running `huggingface-cli login` (stored in `~/.huggingface`). | |
save_peft_format (`bool`, *optional*, defaults to `True`): | |
For backward compatibility with PEFT library, in case adapter weights are attached to the model, all | |
keys of the state dict of adapters needs to be pre-pended with `base_model.model`. Advanced users can | |
disable this behaviours by setting `save_peft_format` to `False`. | |
kwargs (`Dict[str, Any]`, *optional*): | |
Additional key word arguments passed along to the [`~utils.PushToHubMixin.push_to_hub`] method. | |
""" | |
use_auth_token = kwargs.pop("use_auth_token", None) | |
ignore_metadata_errors = kwargs.pop("ignore_metadata_errors", False) | |
if use_auth_token is not None: | |
warnings.warn( | |
"The `use_auth_token` argument is deprecated and will be removed in v5 of Transformers. Please use `token` instead.", | |
FutureWarning, | |
) | |
if token is not None: | |
raise ValueError( | |
"`token` and `use_auth_token` are both specified. Please set only the argument `token`." | |
) | |
token = use_auth_token | |
if token is not None: | |
kwargs["token"] = token | |
_hf_peft_config_loaded = getattr(self, "_hf_peft_config_loaded", False) | |
hf_quantizer = getattr(self, "hf_quantizer", None) | |
quantization_serializable = ( | |
hf_quantizer is not None and isinstance(hf_quantizer, HfQuantizer) and hf_quantizer.is_serializable | |
) | |
if hf_quantizer is not None and not _hf_peft_config_loaded and not quantization_serializable: | |
raise ValueError( | |
f"The model is quantized with {hf_quantizer.quantization_config.quant_method} and is not serializable - check out the warnings from" | |
" the logger on the traceback to understand the reason why the quantized model is not serializable." | |
) | |
if "save_config" in kwargs: | |
warnings.warn( | |
"`save_config` is deprecated and will be removed in v5 of Transformers. Use `is_main_process` instead." | |
) | |
is_main_process = kwargs.pop("save_config") | |
if safe_serialization and not is_safetensors_available(): | |
raise ImportError("`safe_serialization` requires the `safetensors library: `pip install safetensors`.") | |
if os.path.isfile(save_directory): | |
logger.error(f"Provided path ({save_directory}) should be a directory, not a file") | |
return | |
os.makedirs(save_directory, exist_ok=True) | |
if push_to_hub: | |
commit_message = kwargs.pop("commit_message", None) | |
repo_id = kwargs.pop("repo_id", save_directory.split(os.path.sep)[-1]) | |
repo_id = self._create_repo(repo_id, **kwargs) | |
files_timestamps = self._get_files_timestamps(save_directory) | |
# Only save the model itself if we are using distributed training | |
model_to_save = unwrap_model(self) | |
# save the string version of dtype to the config, e.g. convert torch.float32 => "float32" | |
# we currently don't use this setting automatically, but may start to use with v5 | |
dtype = get_parameter_dtype(model_to_save) | |
model_to_save.config.torch_dtype = str(dtype).split(".")[1] | |
# Attach architecture to the config | |
model_to_save.config.architectures = [model_to_save.__class__.__name__] | |
# If we have a custom model, we copy the file defining it in the folder and set the attributes so it can be | |
# loaded from the Hub. | |
if self._auto_class is not None: | |
custom_object_save(self, save_directory, config=self.config) | |
# Save the config | |
if is_main_process: | |
if not _hf_peft_config_loaded: | |
model_to_save.config.save_pretrained(save_directory) | |
if self.can_generate(): | |
# generation config built from the model config + the model config holds generation kwargs -> generate | |
# may revert to legacy behavior if the two don't match | |
if ( | |
model_to_save.generation_config._from_model_config | |
and model_to_save.config._has_non_default_generation_parameters() | |
): | |
new_generation_config = GenerationConfig.from_model_config(model_to_save.config) | |
if new_generation_config != model_to_save.generation_config: | |
logger.warning( | |
"Your generation config was originally created from the model config, but the model " | |
"config has changed since then. Unless you pass the `generation_config` argument to this " | |
"model's `generate` calls, they will revert to the legacy behavior where the base " | |
"`generate` parameterization is loaded from the model config instead. " | |
"To avoid this behavior and this warning, we recommend you to overwrite the generation " | |
"config model attribute before calling the model's `save_pretrained`, preferably also " | |
"removing any generation kwargs from the model config. This warning will be raised to an " | |
"exception in v4.41." | |
) | |
model_to_save.generation_config.save_pretrained(save_directory) | |
if _hf_peft_config_loaded: | |
logger.info( | |
"Detected adapters on the model, saving the model in the PEFT format, only adapter weights will be saved." | |
) | |
state_dict = model_to_save.get_adapter_state_dict() | |
if save_peft_format: | |
logger.info( | |
"To match the expected format of the PEFT library, all keys of the state dict of adapters will be pre-pended with `base_model.model`." | |
) | |
peft_state_dict = {} | |
for key, value in state_dict.items(): | |
peft_state_dict[f"base_model.model.{key}"] = value | |
state_dict = peft_state_dict | |
active_adapter = self.active_adapters() | |
if len(active_adapter) > 1: | |
raise ValueError( | |
"Multiple active adapters detected, saving multiple active adapters is not supported yet. You can save adapters separately one by one " | |
"by iteratively calling `model.set_adapter(adapter_name)` then `model.save_pretrained(...)`" | |
) | |
active_adapter = active_adapter[0] | |
current_peft_config = self.peft_config[active_adapter] | |
current_peft_config.save_pretrained(save_directory) | |
# Save the model | |
if state_dict is None: | |
state_dict = model_to_save.state_dict() | |
# Translate state_dict from smp to hf if saving with smp >= 1.10 | |
if IS_SAGEMAKER_MP_POST_1_10: | |
for smp_to_hf, _ in smp.state.module_manager.translate_functions: | |
state_dict = smp_to_hf(state_dict) | |
# Handle the case where some state_dict keys shouldn't be saved | |
if self._keys_to_ignore_on_save is not None: | |
for ignore_key in self._keys_to_ignore_on_save: | |
if ignore_key in state_dict.keys(): | |
del state_dict[ignore_key] | |
if safe_serialization: | |
# Safetensors does not allow tensor aliasing. | |
# We're going to remove aliases before saving | |
ptrs = collections.defaultdict(list) | |
for name, tensor in state_dict.items(): | |
# Sometimes in the state_dict we have non-tensor objects. | |
# e.g. in bitsandbytes we have some `str` objects in the state_dict | |
if isinstance(tensor, torch.Tensor): | |
ptrs[id_tensor_storage(tensor)].append(name) | |
else: | |
# In the non-tensor case, fall back to the pointer of the object itself | |
ptrs[id(tensor)].append(name) | |
# These are all the pointers of shared tensors. | |
shared_ptrs = {ptr: names for ptr, names in ptrs.items() if len(names) > 1} | |
error_names = [] | |
to_delete_names = set() | |
# Recursively descend to find tied weight keys | |
_tied_weights_keys = _get_tied_weight_keys(self) | |
for names in shared_ptrs.values(): | |
# Removing the keys which are declared as known duplicates on | |
# load. This allows to make sure the name which is kept is consistent. | |
if _tied_weights_keys is not None: | |
found = 0 | |
for name in sorted(names): | |
matches_pattern = any(re.search(pat, name) for pat in _tied_weights_keys) | |
if matches_pattern and name in state_dict: | |
found += 1 | |
if found < len(names): | |
to_delete_names.add(name) | |
# We are entering a place where the weights and the transformers configuration do NOT match. | |
shared_names, disjoint_names = _find_disjoint(shared_ptrs.values(), state_dict) | |
# Those are actually tensor sharing but disjoint from each other, we can safely clone them | |
# Reloaded won't have the same property, but it shouldn't matter in any meaningful way. | |
for name in disjoint_names: | |
state_dict[name] = state_dict[name].clone() | |
# When not all duplicates have been cleaned, still remove those keys, but put a clear warning. | |
# If the link between tensors was done at runtime then `from_pretrained` will not get | |
# the key back leading to random tensor. A proper warning will be shown | |
# during reload (if applicable), but since the file is not necessarily compatible with | |
# the config, better show a proper warning. | |
shared_names, identical_names = _find_identical(shared_names, state_dict) | |
# delete tensors that have identical storage | |
for inames in identical_names: | |
known = inames.intersection(to_delete_names) | |
for name in known: | |
del state_dict[name] | |
unknown = inames.difference(to_delete_names) | |
if len(unknown) > 1: | |
error_names.append(unknown) | |
if shared_names: | |
error_names.append(set(shared_names)) | |
if len(error_names) > 0: | |
raise RuntimeError( | |
f"The weights trying to be saved contained shared tensors {error_names} that are mismatching the transformers base configuration. Try saving using `safe_serialization=False` or remove this tensor sharing.", | |
) | |
# Shard the model if it is too big. | |
if not _hf_peft_config_loaded: | |
weights_name = SAFE_WEIGHTS_NAME if safe_serialization else WEIGHTS_NAME | |
weights_name = _add_variant(weights_name, variant) | |
else: | |
weights_name = ADAPTER_SAFE_WEIGHTS_NAME if safe_serialization else ADAPTER_WEIGHTS_NAME | |
shards, index = shard_checkpoint(state_dict, max_shard_size=max_shard_size, weights_name=weights_name) | |
# Clean the folder from a previous save | |
for filename in os.listdir(save_directory): | |
full_filename = os.path.join(save_directory, filename) | |
# If we have a shard file that is not going to be replaced, we delete it, but only from the main process | |
# in distributed settings to avoid race conditions. | |
weights_no_suffix = weights_name.replace(".bin", "").replace(".safetensors", "") | |
# make sure that file to be deleted matches format of sharded file, e.g. pytorch_model-00001-of-00005 | |
filename_no_suffix = filename.replace(".bin", "").replace(".safetensors", "") | |
reg = re.compile(r"(.*?)-\d{5}-of-\d{5}") | |
if ( | |
filename.startswith(weights_no_suffix) | |
and os.path.isfile(full_filename) | |
and filename not in shards.keys() | |
and is_main_process | |
and reg.fullmatch(filename_no_suffix) is not None | |
): | |
os.remove(full_filename) | |
# Save the model | |
for shard_file, shard in shards.items(): | |
if safe_serialization: | |
# At some point we will need to deal better with save_function (used for TPU and other distributed | |
# joyfulness), but for now this enough. | |
safe_save_file(shard, os.path.join(save_directory, shard_file), metadata={"format": "pt"}) | |
else: | |
save_function(shard, os.path.join(save_directory, shard_file)) | |
if index is None: | |
path_to_weights = os.path.join(save_directory, weights_name) | |
logger.info(f"Model weights saved in {path_to_weights}") | |
else: | |
save_index_file = SAFE_WEIGHTS_INDEX_NAME if safe_serialization else WEIGHTS_INDEX_NAME | |
save_index_file = os.path.join(save_directory, _add_variant(save_index_file, variant)) | |
# Save the index as well | |
with open(save_index_file, "w", encoding="utf-8") as f: | |
content = json.dumps(index, indent=2, sort_keys=True) + "\n" | |
f.write(content) | |
logger.info( | |
f"The model is bigger than the maximum size per checkpoint ({max_shard_size}) and is going to be " | |
f"split in {len(shards)} checkpoint shards. You can find where each parameters has been saved in the " | |
f"index located at {save_index_file}." | |
) | |
if push_to_hub: | |
# Eventually create an empty model card | |
model_card = create_and_tag_model_card( | |
repo_id, self.model_tags, token=token, ignore_metadata_errors=ignore_metadata_errors | |
) | |
# Update model card if needed: | |
model_card.save(os.path.join(save_directory, "README.md")) | |
self._upload_modified_files( | |
save_directory, | |
repo_id, | |
files_timestamps, | |
commit_message=commit_message, | |
token=token, | |
) | |
def push_to_hub(self, *args, **kwargs): | |
tags = self.model_tags if self.model_tags is not None else [] | |
tags_kwargs = kwargs.get("tags", []) | |
if isinstance(tags_kwargs, str): | |
tags_kwargs = [tags_kwargs] | |
for tag in tags_kwargs: | |
if tag not in tags: | |
tags.append(tag) | |
if tags: | |
kwargs["tags"] = tags | |
return super().push_to_hub(*args, **kwargs) | |
def get_memory_footprint(self, return_buffers=True): | |
r""" | |
Get the memory footprint of a model. This will return the memory footprint of the current model in bytes. | |
Useful to benchmark the memory footprint of the current model and design some tests. Solution inspired from the | |
PyTorch discussions: https://discuss.pytorch.org/t/gpu-memory-that-model-uses/56822/2 | |
Arguments: | |
return_buffers (`bool`, *optional*, defaults to `True`): | |
Whether to return the size of the buffer tensors in the computation of the memory footprint. Buffers | |
are tensors that do not require gradients and not registered as parameters. E.g. mean and std in batch | |
norm layers. Please see: https://discuss.pytorch.org/t/what-pytorch-means-by-buffers/120266/2 | |
""" | |
mem = sum([param.nelement() * param.element_size() for param in self.parameters()]) | |
if return_buffers: | |
mem_bufs = sum([buf.nelement() * buf.element_size() for buf in self.buffers()]) | |
mem = mem + mem_bufs | |
return mem | |
def cuda(self, *args, **kwargs): | |
# Checks if the model has been loaded in 8-bit | |
if getattr(self, "quantization_method", None) == QuantizationMethod.BITS_AND_BYTES: | |
raise ValueError( | |
"Calling `cuda()` is not supported for `4-bit` or `8-bit` quantized models. Please use the model as it is, since the" | |
" model has already been set to the correct devices and casted to the correct `dtype`." | |
) | |
else: | |
return super().cuda(*args, **kwargs) | |
def to(self, *args, **kwargs): | |
# Checks if the model has been loaded in 8-bit | |
if getattr(self, "quantization_method", None) == QuantizationMethod.BITS_AND_BYTES: | |
raise ValueError( | |
"`.to` is not supported for `4-bit` or `8-bit` bitsandbytes models. Please use the model as it is, since the" | |
" model has already been set to the correct devices and casted to the correct `dtype`." | |
) | |
elif getattr(self, "quantization_method", None) == QuantizationMethod.GPTQ: | |
# For GPTQ models, we prevent users from casting the model to another dytpe to restrict unwanted behaviours. | |
# the correct API should be to load the model with the desired dtype directly through `from_pretrained`. | |
dtype_present_in_args = False | |
if "dtype" not in kwargs: | |
for arg in args: | |
if isinstance(arg, torch.dtype): | |
dtype_present_in_args = True | |
break | |
else: | |
dtype_present_in_args = True | |
if dtype_present_in_args: | |
raise ValueError( | |
"You cannot cast a GPTQ model in a new `dtype`. Make sure to load the model using `from_pretrained` using the desired" | |
" `dtype` by passing the correct `torch_dtype` argument." | |
) | |
return super().to(*args, **kwargs) | |
def half(self, *args): | |
# Checks if the model is quantized | |
if getattr(self, "is_quantized", False): | |
raise ValueError( | |
"`.half()` is not supported for quantized model. Please use the model as it is, since the" | |
" model has already been casted to the correct `dtype`." | |
) | |
else: | |
return super().half(*args) | |
def float(self, *args): | |
# Checks if the model is quantized | |
if getattr(self, "is_quantized", False): | |
raise ValueError( | |
"`.float()` is not supported for quantized model. Please use the model as it is, since the" | |
" model has already been casted to the correct `dtype`." | |
) | |
else: | |
return super().float(*args) | |
def from_pretrained( | |
cls, | |
pretrained_model_name_or_path: Optional[Union[str, os.PathLike]], | |
*model_args, | |
config: Optional[Union[PretrainedConfig, str, os.PathLike]] = None, | |
cache_dir: Optional[Union[str, os.PathLike]] = None, | |
ignore_mismatched_sizes: bool = False, | |
force_download: bool = False, | |
local_files_only: bool = False, | |
token: Optional[Union[str, bool]] = None, | |
revision: str = "main", | |
use_safetensors: bool = None, | |
**kwargs, | |
): | |
r""" | |
Instantiate a pretrained pytorch model from a pre-trained model configuration. | |
The model is set in evaluation mode by default using `model.eval()` (Dropout modules are deactivated). To train | |
the model, you should first set it back in training mode with `model.train()`. | |
The warning *Weights from XXX not initialized from pretrained model* means that the weights of XXX do not come | |
pretrained with the rest of the model. It is up to you to train those weights with a downstream fine-tuning | |
task. | |
The warning *Weights from XXX not used in YYY* means that the layer XXX is not used by YYY, therefore those | |
weights are discarded. | |
Parameters: | |
pretrained_model_name_or_path (`str` or `os.PathLike`, *optional*): | |
Can be either: | |
- A string, the *model id* of a pretrained model hosted inside a model repo on huggingface.co. | |
- A path to a *directory* containing model weights saved using | |
[`~PreTrainedModel.save_pretrained`], e.g., `./my_model_directory/`. | |
- A path or url to a *tensorflow index checkpoint file* (e.g, `./tf_model/model.ckpt.index`). In | |
this case, `from_tf` should be set to `True` and a configuration object should be provided as | |
`config` argument. This loading path is slower than converting the TensorFlow checkpoint in a | |
PyTorch model using the provided conversion scripts and loading the PyTorch model afterwards. | |
- A path or url to a model folder containing a *flax checkpoint file* in *.msgpack* format (e.g, | |
`./flax_model/` containing `flax_model.msgpack`). In this case, `from_flax` should be set to | |
`True`. | |
- `None` if you are both providing the configuration and state dictionary (resp. with keyword | |
arguments `config` and `state_dict`). | |
model_args (sequence of positional arguments, *optional*): | |
All remaining positional arguments will be passed to the underlying model's `__init__` method. | |
config (`Union[PretrainedConfig, str, os.PathLike]`, *optional*): | |
Can be either: | |
- an instance of a class derived from [`PretrainedConfig`], | |
- a string or path valid as input to [`~PretrainedConfig.from_pretrained`]. | |
Configuration for the model to use instead of an automatically loaded configuration. Configuration can | |
be automatically loaded when: | |
- The model is a model provided by the library (loaded with the *model id* string of a pretrained | |
model). | |
- The model was saved using [`~PreTrainedModel.save_pretrained`] and is reloaded by supplying the | |
save directory. | |
- The model is loaded by supplying a local directory as `pretrained_model_name_or_path` and a | |
configuration JSON file named *config.json* is found in the directory. | |
state_dict (`Dict[str, torch.Tensor]`, *optional*): | |
A state dictionary to use instead of a state dictionary loaded from saved weights file. | |
This option can be used if you want to create a model from a pretrained configuration but load your own | |
weights. In this case though, you should check if using [`~PreTrainedModel.save_pretrained`] and | |
[`~PreTrainedModel.from_pretrained`] is not a simpler option. | |
cache_dir (`Union[str, os.PathLike]`, *optional*): | |
Path to a directory in which a downloaded pretrained model configuration should be cached if the | |
standard cache should not be used. | |
from_tf (`bool`, *optional*, defaults to `False`): | |
Load the model weights from a TensorFlow checkpoint save file (see docstring of | |
`pretrained_model_name_or_path` argument). | |
from_flax (`bool`, *optional*, defaults to `False`): | |
Load the model weights from a Flax checkpoint save file (see docstring of | |
`pretrained_model_name_or_path` argument). | |
ignore_mismatched_sizes (`bool`, *optional*, defaults to `False`): | |
Whether or not to raise an error if some of the weights from the checkpoint do not have the same size | |
as the weights of the model (if for instance, you are instantiating a model with 10 labels from a | |
checkpoint with 3 labels). | |
force_download (`bool`, *optional*, defaults to `False`): | |
Whether or not to force the (re-)download of the model weights and configuration files, overriding the | |
cached versions if they exist. | |
resume_download (`bool`, *optional*, defaults to `False`): | |
Whether or not to delete incompletely received files. Will attempt to resume the download if such a | |
file exists. | |
proxies (`Dict[str, str]`, *optional*): | |
A dictionary of proxy servers to use by protocol or endpoint, e.g., `{'http': 'foo.bar:3128', | |
'http://hostname': 'foo.bar:4012'}`. The proxies are used on each request. | |
output_loading_info(`bool`, *optional*, defaults to `False`): | |
Whether ot not to also return a dictionary containing missing keys, unexpected keys and error messages. | |
local_files_only(`bool`, *optional*, defaults to `False`): | |
Whether or not to only look at local files (i.e., do not try to download the model). | |
token (`str` or `bool`, *optional*): | |
The token to use as HTTP bearer authorization for remote files. If `True`, or not specified, will use | |
the token generated when running `huggingface-cli login` (stored in `~/.huggingface`). | |
revision (`str`, *optional*, defaults to `"main"`): | |
The specific model version to use. It can be a branch name, a tag name, or a commit id, since we use a | |
git-based system for storing models and other artifacts on huggingface.co, so `revision` can be any | |
identifier allowed by git. | |
<Tip> | |
To test a pull request you made on the Hub, you can pass `revision="refs/pr/<pr_number>". | |
</Tip> | |
mirror (`str`, *optional*): | |
Mirror source to accelerate downloads in China. If you are from China and have an accessibility | |
problem, you can set this option to resolve it. Note that we do not guarantee the timeliness or safety. | |
Please refer to the mirror site for more information. | |
_fast_init(`bool`, *optional*, defaults to `True`): | |
Whether or not to disable fast initialization. | |
<Tip warning={true}> | |
One should only disable *_fast_init* to ensure backwards compatibility with `transformers.__version__ < | |
4.6.0` for seeded model initialization. This argument will be removed at the next major version. See | |
[pull request 11471](https://github.com/huggingface/transformers/pull/11471) for more information. | |
</Tip> | |
attn_implementation (`str`, *optional*): | |
The attention implementation to use in the model (if relevant). Can be any of `"eager"` (manual implementation of the attention), `"sdpa"` (using [`F.scaled_dot_product_attention`](https://pytorch.org/docs/master/generated/torch.nn.functional.scaled_dot_product_attention.html)), or `"flash_attention_2"` (using [Dao-AILab/flash-attention](https://github.com/Dao-AILab/flash-attention)). By default, if available, SDPA will be used for torch>=2.1.1. The default is otherwise the manual `"eager"` implementation. | |
> Parameters for big model inference | |
low_cpu_mem_usage(`bool`, *optional*): | |
Tries to not use more than 1x model size in CPU memory (including peak memory) while loading the model. | |
This is an experimental feature and a subject to change at any moment. | |
torch_dtype (`str` or `torch.dtype`, *optional*): | |
Override the default `torch.dtype` and load the model under a specific `dtype`. The different options | |
are: | |
1. `torch.float16` or `torch.bfloat16` or `torch.float`: load in a specified | |
`dtype`, ignoring the model's `config.torch_dtype` if one exists. If not specified | |
- the model will get loaded in `torch.float` (fp32). | |
2. `"auto"` - A `torch_dtype` entry in the `config.json` file of the model will be | |
attempted to be used. If this entry isn't found then next check the `dtype` of the first weight in | |
the checkpoint that's of a floating point type and use that as `dtype`. This will load the model | |
using the `dtype` it was saved in at the end of the training. It can't be used as an indicator of how | |
the model was trained. Since it could be trained in one of half precision dtypes, but saved in fp32. | |
<Tip> | |
For some models the `dtype` they were trained in is unknown - you may try to check the model's paper or | |
reach out to the authors and ask them to add this information to the model's card and to insert the | |
`torch_dtype` entry in `config.json` on the hub. | |
</Tip> | |
device_map (`str` or `Dict[str, Union[int, str, torch.device]]` or `int` or `torch.device`, *optional*): | |
A map that specifies where each submodule should go. It doesn't need to be refined to each | |
parameter/buffer name, once a given module name is inside, every submodule of it will be sent to the | |
same device. If we only pass the device (*e.g.*, `"cpu"`, `"cuda:1"`, `"mps"`, or a GPU ordinal rank | |
like `1`) on which the model will be allocated, the device map will map the entire model to this | |
device. Passing `device_map = 0` means put the whole model on GPU 0. | |
To have Accelerate compute the most optimized `device_map` automatically, set `device_map="auto"`. For | |
more information about each option see [designing a device | |
map](https://hf.co/docs/accelerate/main/en/usage_guides/big_modeling#designing-a-device-map). | |
max_memory (`Dict`, *optional*): | |
A dictionary device identifier to maximum memory. Will default to the maximum memory available for each | |
GPU and the available CPU RAM if unset. | |
offload_folder (`str` or `os.PathLike`, *optional*): | |
If the `device_map` contains any value `"disk"`, the folder where we will offload weights. | |
offload_state_dict (`bool`, *optional*): | |
If `True`, will temporarily offload the CPU state dict to the hard drive to avoid getting out of CPU | |
RAM if the weight of the CPU state dict + the biggest shard of the checkpoint does not fit. Defaults to | |
`True` when there is some disk offload. | |
offload_buffers (`bool`, *optional*): | |
Whether or not to offload the buffers with the model parameters. | |
quantization_config (`Union[QuantizationConfigMixin,Dict]`, *optional*): | |
A dictionary of configuration parameters or a QuantizationConfigMixin object for quantization (e.g | |
bitsandbytes, gptq). There may be other quantization-related kwargs, including `load_in_4bit` and | |
`load_in_8bit`, which are parsed by QuantizationConfigParser. Supported only for bitsandbytes | |
quantizations and not preferred. consider inserting all such arguments into quantization_config | |
instead. | |
subfolder (`str`, *optional*, defaults to `""`): | |
In case the relevant files are located inside a subfolder of the model repo on huggingface.co, you can | |
specify the folder name here. | |
variant (`str`, *optional*): | |
If specified load weights from `variant` filename, *e.g.* pytorch_model.<variant>.bin. `variant` is | |
ignored when using `from_tf` or `from_flax`. | |
use_safetensors (`bool`, *optional*, defaults to `None`): | |
Whether or not to use `safetensors` checkpoints. Defaults to `None`. If not specified and `safetensors` | |
is not installed, it will be set to `False`. | |
kwargs (remaining dictionary of keyword arguments, *optional*): | |
Can be used to update the configuration object (after it being loaded) and initiate the model (e.g., | |
`output_attentions=True`). Behaves differently depending on whether a `config` is provided or | |
automatically loaded: | |
- If a configuration is provided with `config`, `**kwargs` will be directly passed to the | |
underlying model's `__init__` method (we assume all relevant updates to the configuration have | |
already been done) | |
- If a configuration is not provided, `kwargs` will be first passed to the configuration class | |
initialization function ([`~PretrainedConfig.from_pretrained`]). Each key of `kwargs` that | |
corresponds to a configuration attribute will be used to override said attribute with the | |
supplied `kwargs` value. Remaining keys that do not correspond to any configuration attribute | |
will be passed to the underlying model's `__init__` function. | |
<Tip> | |
Activate the special ["offline-mode"](https://huggingface.co/transformers/installation.html#offline-mode) to | |
use this method in a firewalled environment. | |
</Tip> | |
Examples: | |
```python | |
>>> from transformers import BertConfig, BertModel | |
>>> # Download model and configuration from huggingface.co and cache. | |
>>> model = BertModel.from_pretrained("google-bert/bert-base-uncased") | |
>>> # Model was saved using *save_pretrained('./test/saved_model/')* (for example purposes, not runnable). | |
>>> model = BertModel.from_pretrained("./test/saved_model/") | |
>>> # Update configuration during loading. | |
>>> model = BertModel.from_pretrained("google-bert/bert-base-uncased", output_attentions=True) | |
>>> assert model.config.output_attentions == True | |
>>> # Loading from a TF checkpoint file instead of a PyTorch model (slower, for example purposes, not runnable). | |
>>> config = BertConfig.from_json_file("./tf_model/my_tf_model_config.json") | |
>>> model = BertModel.from_pretrained("./tf_model/my_tf_checkpoint.ckpt.index", from_tf=True, config=config) | |
>>> # Loading from a Flax checkpoint file instead of a PyTorch model (slower) | |
>>> model = BertModel.from_pretrained("google-bert/bert-base-uncased", from_flax=True) | |
``` | |
* `low_cpu_mem_usage` algorithm: | |
This is an experimental function that loads the model using ~1x model size CPU memory | |
Here is how it works: | |
1. save which state_dict keys we have | |
2. drop state_dict before the model is created, since the latter takes 1x model size CPU memory | |
3. after the model has been instantiated switch to the meta device all params/buffers that | |
are going to be replaced from the loaded state_dict | |
4. load state_dict 2nd time | |
5. replace the params/buffers from the state_dict | |
Currently, it can't handle deepspeed ZeRO stage 3 and ignores loading errors | |
""" | |
state_dict = kwargs.pop("state_dict", None) | |
from_tf = kwargs.pop("from_tf", False) | |
from_flax = kwargs.pop("from_flax", False) | |
resume_download = kwargs.pop("resume_download", False) | |
proxies = kwargs.pop("proxies", None) | |
output_loading_info = kwargs.pop("output_loading_info", False) | |
use_auth_token = kwargs.pop("use_auth_token", None) | |
trust_remote_code = kwargs.pop("trust_remote_code", None) | |
_ = kwargs.pop("mirror", None) | |
from_pipeline = kwargs.pop("_from_pipeline", None) | |
from_auto_class = kwargs.pop("_from_auto", False) | |
_fast_init = kwargs.pop("_fast_init", True) | |
torch_dtype = kwargs.pop("torch_dtype", None) | |
low_cpu_mem_usage = kwargs.pop("low_cpu_mem_usage", None) | |
device_map = kwargs.pop("device_map", None) | |
max_memory = kwargs.pop("max_memory", None) | |
offload_folder = kwargs.pop("offload_folder", None) | |
offload_state_dict = kwargs.pop("offload_state_dict", False) | |
offload_buffers = kwargs.pop("offload_buffers", False) | |
load_in_8bit = kwargs.pop("load_in_8bit", False) | |
load_in_4bit = kwargs.pop("load_in_4bit", False) | |
quantization_config = kwargs.pop("quantization_config", None) | |
subfolder = kwargs.pop("subfolder", "") | |
commit_hash = kwargs.pop("_commit_hash", None) | |
variant = kwargs.pop("variant", None) | |
adapter_kwargs = kwargs.pop("adapter_kwargs", {}) | |
adapter_name = kwargs.pop("adapter_name", "default") | |
use_flash_attention_2 = kwargs.pop("use_flash_attention_2", False) | |
if is_fsdp_enabled(): | |
low_cpu_mem_usage = True | |
if use_auth_token is not None: | |
warnings.warn( | |
"The `use_auth_token` argument is deprecated and will be removed in v5 of Transformers. Please use `token` instead.", | |
FutureWarning, | |
) | |
if token is not None: | |
raise ValueError( | |
"`token` and `use_auth_token` are both specified. Please set only the argument `token`." | |
) | |
token = use_auth_token | |
if token is not None and adapter_kwargs is not None and "token" not in adapter_kwargs: | |
adapter_kwargs["token"] = token | |
if use_safetensors is None and not is_safetensors_available(): | |
use_safetensors = False | |
if trust_remote_code is True: | |
logger.warning( | |
"The argument `trust_remote_code` is to be used with Auto classes. It has no effect here and is" | |
" ignored." | |
) | |
if commit_hash is None: | |
if not isinstance(config, PretrainedConfig): | |
# We make a call to the config file first (which may be absent) to get the commit hash as soon as possible | |
resolved_config_file = cached_file( | |
pretrained_model_name_or_path, | |
CONFIG_NAME, | |
cache_dir=cache_dir, | |
force_download=force_download, | |
resume_download=resume_download, | |
proxies=proxies, | |
local_files_only=local_files_only, | |
token=token, | |
revision=revision, | |
subfolder=subfolder, | |
_raise_exceptions_for_gated_repo=False, | |
_raise_exceptions_for_missing_entries=False, | |
_raise_exceptions_for_connection_errors=False, | |
) | |
commit_hash = extract_commit_hash(resolved_config_file, commit_hash) | |
else: | |
commit_hash = getattr(config, "_commit_hash", None) | |
if is_peft_available(): | |
_adapter_model_path = adapter_kwargs.pop("_adapter_model_path", None) | |
if _adapter_model_path is None: | |
_adapter_model_path = find_adapter_config_file( | |
pretrained_model_name_or_path, | |
cache_dir=cache_dir, | |
force_download=force_download, | |
resume_download=resume_download, | |
proxies=proxies, | |
local_files_only=local_files_only, | |
_commit_hash=commit_hash, | |
**adapter_kwargs, | |
) | |
if _adapter_model_path is not None and os.path.isfile(_adapter_model_path): | |
with open(_adapter_model_path, "r", encoding="utf-8") as f: | |
_adapter_model_path = pretrained_model_name_or_path | |
pretrained_model_name_or_path = json.load(f)["base_model_name_or_path"] | |
else: | |
_adapter_model_path = None | |
# change device_map into a map if we passed an int, a str or a torch.device | |
if isinstance(device_map, torch.device): | |
device_map = {"": device_map} | |
elif isinstance(device_map, str) and device_map not in ["auto", "balanced", "balanced_low_0", "sequential"]: | |
try: | |
device_map = {"": torch.device(device_map)} | |
except RuntimeError: | |
raise ValueError( | |
"When passing device_map as a string, the value needs to be a device name (e.g. cpu, cuda:0) or " | |
f"'auto', 'balanced', 'balanced_low_0', 'sequential' but found {device_map}." | |
) | |
elif isinstance(device_map, int): | |
if device_map < 0: | |
raise ValueError( | |
"You can't pass device_map as a negative int. If you want to put the model on the cpu, pass device_map = 'cpu' " | |
) | |
else: | |
device_map = {"": device_map} | |
if device_map is not None: | |
if low_cpu_mem_usage is None: | |
low_cpu_mem_usage = True | |
elif not low_cpu_mem_usage: | |
raise ValueError("Passing along a `device_map` requires `low_cpu_mem_usage=True`") | |
if low_cpu_mem_usage: | |
if is_deepspeed_zero3_enabled(): | |
raise ValueError( | |
"DeepSpeed Zero-3 is not compatible with `low_cpu_mem_usage=True` or with passing a `device_map`." | |
) | |
elif not is_accelerate_available(): | |
raise ImportError( | |
"Using `low_cpu_mem_usage=True` or a `device_map` requires Accelerate: `pip install accelerate`" | |
) | |
# handling bnb config from kwargs, remove after `load_in_{4/8}bit` deprecation. | |
if load_in_4bit or load_in_8bit: | |
if quantization_config is not None: | |
raise ValueError( | |
"You can't pass `load_in_4bit`or `load_in_8bit` as a kwarg when passing " | |
"`quantization_config` argument at the same time." | |
) | |
# preparing BitsAndBytesConfig from kwargs | |
config_dict = {k: v for k, v in kwargs.items() if k in inspect.signature(BitsAndBytesConfig).parameters} | |
config_dict = {**config_dict, "load_in_4bit": load_in_4bit, "load_in_8bit": load_in_8bit} | |
quantization_config, kwargs = BitsAndBytesConfig.from_dict( | |
config_dict=config_dict, return_unused_kwargs=True, **kwargs | |
) | |
logger.warning( | |
"The `load_in_4bit` and `load_in_8bit` arguments are deprecated and will be removed in the future versions. " | |
"Please, pass a `BitsAndBytesConfig` object in `quantization_config` argument instead." | |
) | |
from_pt = not (from_tf | from_flax) | |
user_agent = {"file_type": "model", "framework": "pytorch", "from_auto_class": from_auto_class} | |
if from_pipeline is not None: | |
user_agent["using_pipeline"] = from_pipeline | |
if is_offline_mode() and not local_files_only: | |
logger.info("Offline mode: forcing local_files_only=True") | |
local_files_only = True | |
# Load config if we don't provide a configuration | |
if not isinstance(config, PretrainedConfig): | |
config_path = config if config is not None else pretrained_model_name_or_path | |
config, model_kwargs = cls.config_class.from_pretrained( | |
config_path, | |
cache_dir=cache_dir, | |
return_unused_kwargs=True, | |
force_download=force_download, | |
resume_download=resume_download, | |
proxies=proxies, | |
local_files_only=local_files_only, | |
token=token, | |
revision=revision, | |
subfolder=subfolder, | |
_from_auto=from_auto_class, | |
_from_pipeline=from_pipeline, | |
**kwargs, | |
) | |
else: | |
# In case one passes a config to `from_pretrained` + "attn_implementation" | |
# override the `_attn_implementation` attribute to `attn_implementation` of the kwargs | |
# Please see: https://github.com/huggingface/transformers/issues/28038 | |
# Overwrite `config._attn_implementation` by the one from the kwargs --> in auto-factory | |
# we pop attn_implementation from the kwargs but this handles the case where users | |
# passes manually the config to `from_pretrained`. | |
config = copy.deepcopy(config) | |
kwarg_attn_imp = kwargs.pop("attn_implementation", None) | |
if kwarg_attn_imp is not None: | |
config._attn_implementation = kwarg_attn_imp | |
model_kwargs = kwargs | |
pre_quantized = getattr(config, "quantization_config", None) is not None | |
if pre_quantized or quantization_config is not None: | |
if pre_quantized: | |
config.quantization_config = AutoHfQuantizer.merge_quantization_configs( | |
config.quantization_config, quantization_config | |
) | |
else: | |
config.quantization_config = quantization_config | |
hf_quantizer = AutoHfQuantizer.from_config(config.quantization_config, pre_quantized=pre_quantized) | |
else: | |
hf_quantizer = None | |
if hf_quantizer is not None: | |
hf_quantizer.validate_environment( | |
torch_dtype=torch_dtype, from_tf=from_tf, from_flax=from_flax, device_map=device_map | |
) | |
torch_dtype = hf_quantizer.update_torch_dtype(torch_dtype) | |
device_map = hf_quantizer.update_device_map(device_map) | |
# Force-set to `True` for more mem efficiency | |
if low_cpu_mem_usage is None: | |
low_cpu_mem_usage = True | |
logger.warning("`low_cpu_mem_usage` was None, now set to True since model is quantized.") | |
is_quantized = hf_quantizer is not None | |
# This variable will flag if we're loading a sharded checkpoint. In this case the archive file is just the | |
# index of the files. | |
is_sharded = False | |
sharded_metadata = None | |
# Load model | |
loading_info = None | |
# Keep in fp32 modules | |
keep_in_fp32_modules = None | |
use_keep_in_fp32_modules = False | |
if pretrained_model_name_or_path is not None: | |
pretrained_model_name_or_path = str(pretrained_model_name_or_path) | |
is_local = os.path.isdir(pretrained_model_name_or_path) | |
if is_local: | |
if from_tf and os.path.isfile( | |
os.path.join(pretrained_model_name_or_path, subfolder, TF_WEIGHTS_NAME + ".index") | |
): | |
# Load from a TF 1.0 checkpoint in priority if from_tf | |
archive_file = os.path.join(pretrained_model_name_or_path, subfolder, TF_WEIGHTS_NAME + ".index") | |
elif from_tf and os.path.isfile( | |
os.path.join(pretrained_model_name_or_path, subfolder, TF2_WEIGHTS_NAME) | |
): | |
# Load from a TF 2.0 checkpoint in priority if from_tf | |
archive_file = os.path.join(pretrained_model_name_or_path, subfolder, TF2_WEIGHTS_NAME) | |
elif from_flax and os.path.isfile( | |
os.path.join(pretrained_model_name_or_path, subfolder, FLAX_WEIGHTS_NAME) | |
): | |
# Load from a Flax checkpoint in priority if from_flax | |
archive_file = os.path.join(pretrained_model_name_or_path, subfolder, FLAX_WEIGHTS_NAME) | |
elif use_safetensors is not False and os.path.isfile( | |
os.path.join(pretrained_model_name_or_path, subfolder, _add_variant(SAFE_WEIGHTS_NAME, variant)) | |
): | |
# Load from a safetensors checkpoint | |
archive_file = os.path.join( | |
pretrained_model_name_or_path, subfolder, _add_variant(SAFE_WEIGHTS_NAME, variant) | |
) | |
elif use_safetensors is not False and os.path.isfile( | |
os.path.join( | |
pretrained_model_name_or_path, subfolder, _add_variant(SAFE_WEIGHTS_INDEX_NAME, variant) | |
) | |
): | |
# Load from a sharded safetensors checkpoint | |
archive_file = os.path.join( | |
pretrained_model_name_or_path, subfolder, _add_variant(SAFE_WEIGHTS_INDEX_NAME, variant) | |
) | |
is_sharded = True | |
elif os.path.isfile( | |
os.path.join(pretrained_model_name_or_path, subfolder, _add_variant(WEIGHTS_NAME, variant)) | |
): | |
# Load from a PyTorch checkpoint | |
archive_file = os.path.join( | |
pretrained_model_name_or_path, subfolder, _add_variant(WEIGHTS_NAME, variant) | |
) | |
elif os.path.isfile( | |
os.path.join(pretrained_model_name_or_path, subfolder, _add_variant(WEIGHTS_INDEX_NAME, variant)) | |
): | |
# Load from a sharded PyTorch checkpoint | |
archive_file = os.path.join( | |
pretrained_model_name_or_path, subfolder, _add_variant(WEIGHTS_INDEX_NAME, variant) | |
) | |
is_sharded = True | |
# At this stage we don't have a weight file so we will raise an error. | |
elif os.path.isfile( | |
os.path.join(pretrained_model_name_or_path, subfolder, TF_WEIGHTS_NAME + ".index") | |
) or os.path.isfile(os.path.join(pretrained_model_name_or_path, subfolder, TF2_WEIGHTS_NAME)): | |
raise EnvironmentError( | |
f"Error no file named {_add_variant(WEIGHTS_NAME, variant)} found in directory" | |
f" {pretrained_model_name_or_path} but there is a file for TensorFlow weights. Use" | |
" `from_tf=True` to load this model from those weights." | |
) | |
elif os.path.isfile(os.path.join(pretrained_model_name_or_path, subfolder, FLAX_WEIGHTS_NAME)): | |
raise EnvironmentError( | |
f"Error no file named {_add_variant(WEIGHTS_NAME, variant)} found in directory" | |
f" {pretrained_model_name_or_path} but there is a file for Flax weights. Use `from_flax=True`" | |
" to load this model from those weights." | |
) | |
elif use_safetensors: | |
raise EnvironmentError( | |
f"Error no file named {_add_variant(SAFE_WEIGHTS_NAME, variant)} found in directory" | |
f" {pretrained_model_name_or_path}." | |
) | |
else: | |
raise EnvironmentError( | |
f"Error no file named {_add_variant(WEIGHTS_NAME, variant)}, {TF2_WEIGHTS_NAME}," | |
f" {TF_WEIGHTS_NAME + '.index'} or {FLAX_WEIGHTS_NAME} found in directory" | |
f" {pretrained_model_name_or_path}." | |
) | |
elif os.path.isfile(os.path.join(subfolder, pretrained_model_name_or_path)): | |
archive_file = pretrained_model_name_or_path | |
is_local = True | |
elif os.path.isfile(os.path.join(subfolder, pretrained_model_name_or_path + ".index")): | |
if not from_tf: | |
raise ValueError( | |
f"We found a TensorFlow checkpoint at {pretrained_model_name_or_path + '.index'}, please set " | |
"from_tf to True to load from this checkpoint." | |
) | |
archive_file = os.path.join(subfolder, pretrained_model_name_or_path + ".index") | |
is_local = True | |
elif is_remote_url(pretrained_model_name_or_path): | |
filename = pretrained_model_name_or_path | |
resolved_archive_file = download_url(pretrained_model_name_or_path) | |
else: | |
# set correct filename | |
if from_tf: | |
filename = TF2_WEIGHTS_NAME | |
elif from_flax: | |
filename = FLAX_WEIGHTS_NAME | |
elif use_safetensors is not False: | |
filename = _add_variant(SAFE_WEIGHTS_NAME, variant) | |
else: | |
filename = _add_variant(WEIGHTS_NAME, variant) | |
try: | |
# Load from URL or cache if already cached | |
cached_file_kwargs = { | |
"cache_dir": cache_dir, | |
"force_download": force_download, | |
"proxies": proxies, | |
"resume_download": resume_download, | |
"local_files_only": local_files_only, | |
"token": token, | |
"user_agent": user_agent, | |
"revision": revision, | |
"subfolder": subfolder, | |
"_raise_exceptions_for_gated_repo": False, | |
"_raise_exceptions_for_missing_entries": False, | |
"_commit_hash": commit_hash, | |
} | |
resolved_archive_file = cached_file(pretrained_model_name_or_path, filename, **cached_file_kwargs) | |
# Since we set _raise_exceptions_for_missing_entries=False, we don't get an exception but a None | |
# result when internet is up, the repo and revision exist, but the file does not. | |
if resolved_archive_file is None and filename == _add_variant(SAFE_WEIGHTS_NAME, variant): | |
# Maybe the checkpoint is sharded, we try to grab the index name in this case. | |
resolved_archive_file = cached_file( | |
pretrained_model_name_or_path, | |
_add_variant(SAFE_WEIGHTS_INDEX_NAME, variant), | |
**cached_file_kwargs, | |
) | |
if resolved_archive_file is not None: | |
is_sharded = True | |
elif use_safetensors: | |
if revision == "main": | |
resolved_archive_file, revision, is_sharded = auto_conversion( | |
pretrained_model_name_or_path, **cached_file_kwargs | |
) | |
cached_file_kwargs["revision"] = revision | |
if resolved_archive_file is None: | |
raise EnvironmentError( | |
f"{pretrained_model_name_or_path} does not appear to have a file named" | |
f" {_add_variant(SAFE_WEIGHTS_NAME, variant)} or {_add_variant(SAFE_WEIGHTS_INDEX_NAME, variant)} " | |
"and thus cannot be loaded with `safetensors`. Please make sure that the model has " | |
"been saved with `safe_serialization=True` or do not set `use_safetensors=True`." | |
) | |
else: | |
# This repo has no safetensors file of any kind, we switch to PyTorch. | |
filename = _add_variant(WEIGHTS_NAME, variant) | |
resolved_archive_file = cached_file( | |
pretrained_model_name_or_path, filename, **cached_file_kwargs | |
) | |
if resolved_archive_file is None and filename == _add_variant(WEIGHTS_NAME, variant): | |
# Maybe the checkpoint is sharded, we try to grab the index name in this case. | |
resolved_archive_file = cached_file( | |
pretrained_model_name_or_path, | |
_add_variant(WEIGHTS_INDEX_NAME, variant), | |
**cached_file_kwargs, | |
) | |
if resolved_archive_file is not None: | |
is_sharded = True | |
if resolved_archive_file is not None: | |
if filename in [WEIGHTS_NAME, WEIGHTS_INDEX_NAME]: | |
# If the PyTorch file was found, check if there is a safetensors file on the repository | |
# If there is no safetensors file on the repositories, start an auto conversion | |
safe_weights_name = SAFE_WEIGHTS_INDEX_NAME if is_sharded else SAFE_WEIGHTS_NAME | |
has_file_kwargs = { | |
"revision": revision, | |
"proxies": proxies, | |
"token": token, | |
} | |
cached_file_kwargs = { | |
"cache_dir": cache_dir, | |
"force_download": force_download, | |
"resume_download": resume_download, | |
"local_files_only": local_files_only, | |
"user_agent": user_agent, | |
"subfolder": subfolder, | |
"_raise_exceptions_for_gated_repo": False, | |
"_raise_exceptions_for_missing_entries": False, | |
"_commit_hash": commit_hash, | |
**has_file_kwargs, | |
} | |
if not has_file(pretrained_model_name_or_path, safe_weights_name, **has_file_kwargs): | |
Thread( | |
target=auto_conversion, | |
args=(pretrained_model_name_or_path,), | |
kwargs={"ignore_errors_during_conversion": True, **cached_file_kwargs}, | |
name="Thread-autoconversion", | |
).start() | |
else: | |
# Otherwise, no PyTorch file was found, maybe there is a TF or Flax model file. | |
# We try those to give a helpful error message. | |
has_file_kwargs = { | |
"revision": revision, | |
"proxies": proxies, | |
"token": token, | |
} | |
if has_file(pretrained_model_name_or_path, TF2_WEIGHTS_NAME, **has_file_kwargs): | |
raise EnvironmentError( | |
f"{pretrained_model_name_or_path} does not appear to have a file named" | |
f" {_add_variant(WEIGHTS_NAME, variant)} but there is a file for TensorFlow weights." | |
" Use `from_tf=True` to load this model from those weights." | |
) | |
elif has_file(pretrained_model_name_or_path, FLAX_WEIGHTS_NAME, **has_file_kwargs): | |
raise EnvironmentError( | |
f"{pretrained_model_name_or_path} does not appear to have a file named" | |
f" {_add_variant(WEIGHTS_NAME, variant)} but there is a file for Flax weights. Use" | |
" `from_flax=True` to load this model from those weights." | |
) | |
elif variant is not None and has_file( | |
pretrained_model_name_or_path, WEIGHTS_NAME, **has_file_kwargs | |
): | |
raise EnvironmentError( | |
f"{pretrained_model_name_or_path} does not appear to have a file named" | |
f" {_add_variant(WEIGHTS_NAME, variant)} but there is a file without the variant" | |
f" {variant}. Use `variant=None` to load this model from those weights." | |
) | |
else: | |
raise EnvironmentError( | |
f"{pretrained_model_name_or_path} does not appear to have a file named" | |
f" {_add_variant(WEIGHTS_NAME, variant)}, {TF2_WEIGHTS_NAME}, {TF_WEIGHTS_NAME} or" | |
f" {FLAX_WEIGHTS_NAME}." | |
) | |
except EnvironmentError: | |
# Raise any environment error raise by `cached_file`. It will have a helpful error message adapted | |
# to the original exception. | |
raise | |
except Exception as e: | |
# For any other exception, we throw a generic error. | |
raise EnvironmentError( | |
f"Can't load the model for '{pretrained_model_name_or_path}'. If you were trying to load it" | |
" from 'https://huggingface.co/models', make sure you don't have a local directory with the" | |
f" same name. Otherwise, make sure '{pretrained_model_name_or_path}' is the correct path to a" | |
f" directory containing a file named {_add_variant(WEIGHTS_NAME, variant)}," | |
f" {TF2_WEIGHTS_NAME}, {TF_WEIGHTS_NAME} or {FLAX_WEIGHTS_NAME}." | |
) from e | |
if is_local: | |
logger.info(f"loading weights file {archive_file}") | |
resolved_archive_file = archive_file | |
else: | |
logger.info(f"loading weights file {filename} from cache at {resolved_archive_file}") | |
else: | |
resolved_archive_file = None | |
# We'll need to download and cache each checkpoint shard if the checkpoint is sharded. | |
if is_sharded: | |
# rsolved_archive_file becomes a list of files that point to the different checkpoint shards in this case. | |
resolved_archive_file, sharded_metadata = get_checkpoint_shard_files( | |
pretrained_model_name_or_path, | |
resolved_archive_file, | |
cache_dir=cache_dir, | |
force_download=force_download, | |
proxies=proxies, | |
resume_download=resume_download, | |
local_files_only=local_files_only, | |
token=token, | |
user_agent=user_agent, | |
revision=revision, | |
subfolder=subfolder, | |
_commit_hash=commit_hash, | |
) | |
if ( | |
is_safetensors_available() | |
and isinstance(resolved_archive_file, str) | |
and resolved_archive_file.endswith(".safetensors") | |
): | |
with safe_open(resolved_archive_file, framework="pt") as f: | |
metadata = f.metadata() | |
if metadata.get("format") == "pt": | |
pass | |
elif metadata.get("format") == "tf": | |
from_tf = True | |
logger.info("A TensorFlow safetensors file is being loaded in a PyTorch model.") | |
elif metadata.get("format") == "flax": | |
from_flax = True | |
logger.info("A Flax safetensors file is being loaded in a PyTorch model.") | |
elif metadata.get("format") == "mlx": | |
# This is a mlx file, we assume weights are compatible with pt | |
pass | |
else: | |
raise ValueError( | |
f"Incompatible safetensors file. File metadata is not ['pt', 'tf', 'flax', 'mlx'] but {metadata.get('format')}" | |
) | |
from_pt = not (from_tf | from_flax) | |
# load pt weights early so that we know which dtype to init the model under | |
if from_pt: | |
if not is_sharded and state_dict is None: | |
# Time to load the checkpoint | |
state_dict = load_state_dict(resolved_archive_file) | |
# set dtype to instantiate the model under: | |
# 1. If torch_dtype is not None, we use that dtype | |
# 2. If torch_dtype is "auto", we auto-detect dtype from the loaded state_dict, by checking its first | |
# weights entry that is of a floating type - we assume all floating dtype weights are of the same dtype | |
# we also may have config.torch_dtype available, but we won't rely on it till v5 | |
dtype_orig = None | |
if torch_dtype is not None: | |
if isinstance(torch_dtype, str): | |
if torch_dtype == "auto": | |
if hasattr(config, "torch_dtype") and config.torch_dtype is not None: | |
torch_dtype = config.torch_dtype | |
logger.info(f"Will use torch_dtype={torch_dtype} as defined in model's config object") | |
else: | |
if is_sharded and "dtype" in sharded_metadata: | |
torch_dtype = sharded_metadata["dtype"] | |
elif not is_sharded: | |
torch_dtype = get_state_dict_dtype(state_dict) | |
else: | |
one_state_dict = load_state_dict(resolved_archive_file[0]) | |
torch_dtype = get_state_dict_dtype(one_state_dict) | |
del one_state_dict # free CPU memory | |
logger.info( | |
"Since the `torch_dtype` attribute can't be found in model's config object, " | |
"will use torch_dtype={torch_dtype} as derived from model's weights" | |
) | |
else: | |
raise ValueError( | |
f'`torch_dtype` can be either `torch.dtype` or `"auto"`, but received {torch_dtype}' | |
) | |
dtype_orig = cls._set_default_torch_dtype(torch_dtype) | |
# Check if `_keep_in_fp32_modules` is not None | |
use_keep_in_fp32_modules = (cls._keep_in_fp32_modules is not None) and ( | |
(torch_dtype == torch.float16) or hasattr(hf_quantizer, "use_keep_in_fp32_modules") | |
) | |
if is_sharded: | |
loaded_state_dict_keys = sharded_metadata["all_checkpoint_keys"] | |
else: | |
loaded_state_dict_keys = list(state_dict.keys()) | |
if low_cpu_mem_usage or (use_keep_in_fp32_modules and is_accelerate_available()): | |
# In case some weights need to be kept in float32 and accelerate is not installed, | |
# we later on want to take the path where state_dict is not None, that is the one | |
# that do not require accelerate. | |
state_dict = None | |
config.name_or_path = pretrained_model_name_or_path | |
# Instantiate model. | |
init_contexts = [no_init_weights(_enable=_fast_init)] | |
if is_deepspeed_zero3_enabled() and not is_quantized: | |
import deepspeed | |
logger.info("Detected DeepSpeed ZeRO-3: activating zero.init() for this model") | |
init_contexts = [deepspeed.zero.Init(config_dict_or_path=deepspeed_config())] + init_contexts | |
elif low_cpu_mem_usage: | |
init_contexts.append(init_empty_weights()) | |
config = copy.deepcopy(config) # We do not want to modify the config inplace in from_pretrained. | |
config = cls._autoset_attn_implementation( | |
config, use_flash_attention_2=use_flash_attention_2, torch_dtype=torch_dtype, device_map=device_map | |
) | |
with ContextManagers(init_contexts): | |
# Let's make sure we don't run the init function of buffer modules | |
model = cls(config, *model_args, **model_kwargs) | |
# make sure we use the model's config since the __init__ call might have copied it | |
config = model.config | |
# Check first if we are `from_pt` | |
if use_keep_in_fp32_modules: | |
if is_accelerate_available() and not is_deepspeed_zero3_enabled(): | |
low_cpu_mem_usage = True | |
keep_in_fp32_modules = model._keep_in_fp32_modules | |
else: | |
keep_in_fp32_modules = [] | |
if hf_quantizer is not None: | |
hf_quantizer.preprocess_model( | |
model=model, device_map=device_map, keep_in_fp32_modules=keep_in_fp32_modules | |
) | |
# We store the original dtype for quantized models as we cannot easily retrieve it | |
# once the weights have been quantized | |
# Note that once you have loaded a quantized model, you can't change its dtype so this will | |
# remain a single source of truth | |
config._pre_quantization_dtype = torch_dtype | |
if isinstance(device_map, str): | |
special_dtypes = {} | |
if hf_quantizer is not None: | |
special_dtypes.update(hf_quantizer.get_special_dtypes_update(model, torch_dtype)) | |
special_dtypes.update( | |
{ | |
name: torch.float32 | |
for name, _ in model.named_parameters() | |
if any(m in name for m in keep_in_fp32_modules) | |
} | |
) | |
target_dtype = torch_dtype | |
if hf_quantizer is not None: | |
target_dtype = hf_quantizer.adjust_target_dtype(target_dtype) | |
no_split_modules = model._get_no_split_modules(device_map) | |
if device_map not in ["auto", "balanced", "balanced_low_0", "sequential"]: | |
raise ValueError( | |
"If passing a string for `device_map`, please choose 'auto', 'balanced', 'balanced_low_0' or " | |
"'sequential'." | |
) | |
device_map_kwargs = {"no_split_module_classes": no_split_modules} | |
if "special_dtypes" in inspect.signature(infer_auto_device_map).parameters: | |
device_map_kwargs["special_dtypes"] = special_dtypes | |
elif len(special_dtypes) > 0: | |
logger.warning( | |
"This model has some weights that should be kept in higher precision, you need to upgrade " | |
"`accelerate` to properly deal with them (`pip install --upgrade accelerate`)." | |
) | |
if device_map != "sequential": | |
max_memory = get_balanced_memory( | |
model, | |
dtype=target_dtype, | |
low_zero=(device_map == "balanced_low_0"), | |
max_memory=max_memory, | |
**device_map_kwargs, | |
) | |
else: | |
max_memory = get_max_memory(max_memory) | |
if hf_quantizer is not None: | |
max_memory = hf_quantizer.adjust_max_memory(max_memory) | |
device_map_kwargs["max_memory"] = max_memory | |
# Make sure tied weights are tied before creating the device map. | |
model.tie_weights() | |
device_map = infer_auto_device_map(model, dtype=target_dtype, **device_map_kwargs) | |
if hf_quantizer is not None: | |
hf_quantizer.validate_environment(device_map=device_map) | |
elif device_map is not None: | |
model.tie_weights() | |
tied_params = find_tied_parameters(model) | |
# check if we don't have tied param in different devices | |
check_tied_parameters_on_same_device(tied_params, device_map) | |
if from_tf: | |
if resolved_archive_file.endswith(".index"): | |
# Load from a TensorFlow 1.X checkpoint - provided by original authors | |
model = cls.load_tf_weights(model, config, resolved_archive_file[:-6]) # Remove the '.index' | |
else: | |
# Load from our TensorFlow 2.0 checkpoints | |
try: | |
from .modeling_tf_pytorch_utils import load_tf2_checkpoint_in_pytorch_model | |
model, loading_info = load_tf2_checkpoint_in_pytorch_model( | |
model, resolved_archive_file, allow_missing_keys=True, output_loading_info=True | |
) | |
except ImportError: | |
logger.error( | |
"Loading a TensorFlow model in PyTorch, requires both PyTorch and TensorFlow to be installed." | |
" Please see https://pytorch.org/ and https://www.tensorflow.org/install/ for installation" | |
" instructions." | |
) | |
raise | |
elif from_flax: | |
try: | |
from .modeling_flax_pytorch_utils import load_flax_checkpoint_in_pytorch_model | |
model = load_flax_checkpoint_in_pytorch_model(model, resolved_archive_file) | |
except ImportError: | |
logger.error( | |
"Loading a Flax model in PyTorch, requires both PyTorch and Flax to be installed. Please see" | |
" https://pytorch.org/ and https://flax.readthedocs.io/en/latest/installation.html for" | |
" installation instructions." | |
) | |
raise | |
elif from_pt: | |
# restore default dtype | |
if dtype_orig is not None: | |
torch.set_default_dtype(dtype_orig) | |
( | |
model, | |
missing_keys, | |
unexpected_keys, | |
mismatched_keys, | |
offload_index, | |
error_msgs, | |
) = cls._load_pretrained_model( | |
model, | |
state_dict, | |
loaded_state_dict_keys, # XXX: rename? | |
resolved_archive_file, | |
pretrained_model_name_or_path, | |
ignore_mismatched_sizes=ignore_mismatched_sizes, | |
sharded_metadata=sharded_metadata, | |
_fast_init=_fast_init, | |
low_cpu_mem_usage=low_cpu_mem_usage, | |
device_map=device_map, | |
offload_folder=offload_folder, | |
offload_state_dict=offload_state_dict, | |
dtype=torch_dtype, | |
hf_quantizer=hf_quantizer, | |
keep_in_fp32_modules=keep_in_fp32_modules, | |
) | |
# make sure token embedding weights are still tied if needed | |
model.tie_weights() | |
# Set model in evaluation mode to deactivate DropOut modules by default | |
model.eval() | |
# If it is a model with generation capabilities, attempt to load the generation config | |
if model.can_generate() and pretrained_model_name_or_path is not None: | |
try: | |
model.generation_config = GenerationConfig.from_pretrained( | |
pretrained_model_name_or_path, | |
cache_dir=cache_dir, | |
force_download=force_download, | |
resume_download=resume_download, | |
proxies=proxies, | |
local_files_only=local_files_only, | |
token=token, | |
revision=revision, | |
subfolder=subfolder, | |
_from_auto=from_auto_class, | |
_from_pipeline=from_pipeline, | |
**kwargs, | |
) | |
except OSError: | |
logger.info( | |
"Generation config file not found, using a generation config created from the model config." | |
) | |
pass | |
# Dispatch model with hooks on all devices if necessary | |
if device_map is not None: | |
device_map_kwargs = { | |
"device_map": device_map, | |
"offload_dir": offload_folder, | |
"offload_index": offload_index, | |
"offload_buffers": offload_buffers, | |
} | |
if "skip_keys" in inspect.signature(dispatch_model).parameters: | |
device_map_kwargs["skip_keys"] = model._skip_keys_device_placement | |
if not is_fsdp_enabled() and not is_deepspeed_zero3_enabled(): | |
dispatch_model(model, **device_map_kwargs) | |
if hf_quantizer is not None: | |
hf_quantizer.postprocess_model(model) | |
model.hf_quantizer = hf_quantizer | |
if _adapter_model_path is not None: | |
model.load_adapter( | |
_adapter_model_path, | |
adapter_name=adapter_name, | |
token=token, | |
adapter_kwargs=adapter_kwargs, | |
) | |
if output_loading_info: | |
if loading_info is None: | |
loading_info = { | |
"missing_keys": missing_keys, | |
"unexpected_keys": unexpected_keys, | |
"mismatched_keys": mismatched_keys, | |
"error_msgs": error_msgs, | |
} | |
return model, loading_info | |
return model | |
def _load_pretrained_model( | |
cls, | |
model, | |
state_dict, | |
loaded_keys, | |
resolved_archive_file, | |
pretrained_model_name_or_path, | |
ignore_mismatched_sizes=False, | |
sharded_metadata=None, | |
_fast_init=True, | |
low_cpu_mem_usage=False, | |
device_map=None, | |
offload_folder=None, | |
offload_state_dict=None, | |
dtype=None, | |
hf_quantizer=None, | |
keep_in_fp32_modules=None, | |
): | |
is_safetensors = False | |
is_quantized = hf_quantizer is not None | |
if device_map is not None and "disk" in device_map.values(): | |
archive_file = ( | |
resolved_archive_file[0] if isinstance(resolved_archive_file, (list, tuple)) else resolved_archive_file | |
) | |
is_safetensors = archive_file.endswith(".safetensors") | |
if offload_folder is None and not is_safetensors: | |
raise ValueError( | |
"The current `device_map` had weights offloaded to the disk. Please provide an `offload_folder`" | |
" for them. Alternatively, make sure you have `safetensors` installed if the model you are using" | |
" offers the weights in this format." | |
) | |
if offload_folder is not None: | |
os.makedirs(offload_folder, exist_ok=True) | |
if offload_state_dict is None: | |
offload_state_dict = True | |
is_sharded_safetensors = is_safetensors and sharded_metadata is not None | |
# tie the model weights before retrieving the state_dict | |
model.tie_weights() | |
# Retrieve missing & unexpected_keys | |
model_state_dict = model.state_dict() | |
expected_keys = list(model_state_dict.keys()) | |
prefix = model.base_model_prefix | |
def _fix_key(key): | |
if "beta" in key: | |
return key.replace("beta", "bias") | |
if "gamma" in key: | |
return key.replace("gamma", "weight") | |
return key | |
original_loaded_keys = loaded_keys | |
loaded_keys = [_fix_key(key) for key in loaded_keys] | |
if len(prefix) > 0: | |
has_prefix_module = any(s.startswith(prefix) for s in loaded_keys) | |
expects_prefix_module = any(s.startswith(prefix) for s in expected_keys) | |
else: | |
has_prefix_module = False | |
expects_prefix_module = False | |
# key re-naming operations are never done on the keys | |
# that are loaded, but always on the keys of the newly initialized model | |
remove_prefix_from_model = not has_prefix_module and expects_prefix_module | |
add_prefix_to_model = has_prefix_module and not expects_prefix_module | |
if remove_prefix_from_model: | |
_prefix = f"{prefix}." | |
expected_keys_not_prefixed = [s for s in expected_keys if not s.startswith(_prefix)] | |
expected_keys = [s[len(_prefix) :] if s.startswith(_prefix) else s for s in expected_keys] | |
elif add_prefix_to_model: | |
expected_keys = [".".join([prefix, s]) for s in expected_keys] | |
missing_keys = sorted(set(expected_keys) - set(loaded_keys)) | |
unexpected_keys = set(loaded_keys) - set(expected_keys) | |
# Remove nonpersistent buffers from unexpected keys: they are not in the state dict but will be in the model | |
# buffers | |
model_buffers = {n for n, _ in model.named_buffers()} | |
if remove_prefix_from_model: | |
model_buffers = {key[len(_prefix) :] if key.startswith(_prefix) else key for key in model_buffers} | |
elif add_prefix_to_model: | |
model_buffers = {".".join([prefix, key]) for key in model_buffers} | |
unexpected_keys = sorted(unexpected_keys - model_buffers) | |
model.tie_weights() | |
if device_map is None and not is_fsdp_enabled() and not is_deepspeed_zero3_enabled(): | |
ptrs = collections.defaultdict(list) | |
for name, tensor in model.state_dict().items(): | |
id_tensor = id_tensor_storage(tensor) | |
ptrs[id_tensor].append(name) | |
# These are all the pointers of shared tensors. | |
tied_params = [names for _, names in ptrs.items() if len(names) > 1] | |
else: | |
# id function doesn't work for meta tensor so we need this function | |
tied_params = find_tied_parameters(model) | |
for group in tied_params: | |
if remove_prefix_from_model: | |
group = [key[len(_prefix) :] if key.startswith(_prefix) else key for key in group] | |
elif add_prefix_to_model: | |
group = [".".join([prefix, key]) for key in group] | |
missing_in_group = [k for k in missing_keys if k in group] | |
if len(missing_in_group) > 0 and len(missing_in_group) < len(group): | |
missing_keys = [k for k in missing_keys if k not in missing_in_group] | |
# Some models may have keys that are not in the state by design, removing them before needlessly warning | |
# the user. | |
if cls._keys_to_ignore_on_load_missing is not None: | |
for pat in cls._keys_to_ignore_on_load_missing: | |
missing_keys = [k for k in missing_keys if re.search(pat, k) is None] | |
if cls._keys_to_ignore_on_load_unexpected is not None: | |
for pat in cls._keys_to_ignore_on_load_unexpected: | |
unexpected_keys = [k for k in unexpected_keys if re.search(pat, k) is None] | |
if hf_quantizer is not None: | |
missing_keys = hf_quantizer.update_missing_keys(model, missing_keys, prefix) | |
# retrieve weights on meta device and put them back on CPU. | |
# This is not ideal in terms of memory, but if we don't do that not, we can't initialize them in the next step | |
if low_cpu_mem_usage: | |
for key in missing_keys: | |
if key in list(model_state_dict.keys()): | |
key = key | |
elif f"{prefix}.{key}" in list(model_state_dict.keys()): | |
key = f"{prefix}.{key}" | |
elif key.startswith(prefix) and ".".join(key.split(".")[1:]) in list(model_state_dict.keys()): | |
key = ".".join(key.split(".")[1:]) | |
param = model_state_dict[key] | |
# upcast in fp32 if any | |
target_dtype = dtype | |
if ( | |
keep_in_fp32_modules is not None | |
and dtype == torch.float16 | |
and any( | |
module_to_keep_in_fp32 in key.split(".") for module_to_keep_in_fp32 in keep_in_fp32_modules | |
) | |
): | |
target_dtype = torch.float32 | |
if param.device == torch.device("meta"): | |
value = torch.empty(*param.size(), dtype=target_dtype) | |
if ( | |
not is_quantized | |
or getattr(hf_quantizer, "requires_parameters_quantization", False) | |
or not hf_quantizer.check_quantized_param( | |
model, param_value=value, param_name=key, state_dict={} | |
) | |
): | |
set_module_tensor_to_device(model, key, "cpu", value) | |
else: | |
hf_quantizer.create_quantized_param(model, value, key, "cpu", state_dict, unexpected_keys) | |
# retrieve uninitialized modules and initialize before maybe overriding that with the pretrained weights. | |
if _fast_init: | |
if not ignore_mismatched_sizes: | |
if remove_prefix_from_model: | |
_loaded_keys = [f"{prefix}.{k}" for k in loaded_keys] | |
elif add_prefix_to_model: | |
_loaded_keys = [k[len(prefix) + 1 :] for k in loaded_keys] | |
else: | |
_loaded_keys = loaded_keys | |
not_initialized_submodules = set_initialized_submodules(model, _loaded_keys) | |
# If we're about to tie the output embeds to the input embeds we don't need to init them | |
if hasattr(model.config, "tie_word_embeddings") and model.config.tie_word_embeddings: | |
output_embeddings = model.get_output_embeddings() | |
if output_embeddings is not None: | |
# Still need to initialize if there is a bias term since biases are not tied. | |
if not hasattr(output_embeddings, "bias") or output_embeddings.bias is None: | |
output_embeddings._is_hf_initialized = True | |
else: | |
not_initialized_submodules = dict(model.named_modules()) | |
# This will only initialize submodules that are not marked as initialized by the line above. | |
if is_deepspeed_zero3_enabled() and not is_quantized: | |
import deepspeed | |
not_initialized_parameters = list( | |
set( | |
itertools.chain.from_iterable( | |
submodule.parameters(recurse=False) for submodule in not_initialized_submodules.values() | |
) | |
) | |
) | |
with deepspeed.zero.GatheredParameters(not_initialized_parameters, modifier_rank=0): | |
model.apply(model._initialize_weights) | |
else: | |
model.apply(model._initialize_weights) | |
# Set some modules to fp32 if any | |
if keep_in_fp32_modules is not None: | |
for name, param in model.named_parameters(): | |
if any(module_to_keep_in_fp32 in name.split(".") for module_to_keep_in_fp32 in keep_in_fp32_modules): | |
# param = param.to(torch.float32) does not work here as only in the local scope. | |
param.data = param.data.to(torch.float32) | |
# Make sure we are able to load base models as well as derived models (with heads) | |
start_prefix = "" | |
model_to_load = model | |
if len(cls.base_model_prefix) > 0 and not hasattr(model, cls.base_model_prefix) and has_prefix_module: | |
start_prefix = cls.base_model_prefix + "." | |
if len(cls.base_model_prefix) > 0 and hasattr(model, cls.base_model_prefix) and not has_prefix_module: | |
model_to_load = getattr(model, cls.base_model_prefix) | |
base_model_expected_keys = list(model_to_load.state_dict().keys()) | |
if any(key in expected_keys_not_prefixed and key not in base_model_expected_keys for key in loaded_keys): | |
raise ValueError( | |
"The state dictionary of the model you are trying to load is corrupted. Are you sure it was " | |
"properly saved?" | |
) | |
if device_map is not None: | |
device_map = {k.replace(f"{cls.base_model_prefix}.", ""): v for k, v in device_map.items()} | |
def _find_mismatched_keys( | |
state_dict, | |
model_state_dict, | |
loaded_keys, | |
add_prefix_to_model, | |
remove_prefix_from_model, | |
ignore_mismatched_sizes, | |
): | |
mismatched_keys = [] | |
if ignore_mismatched_sizes: | |
for checkpoint_key in loaded_keys: | |
# If the checkpoint is sharded, we may not have the key here. | |
if checkpoint_key not in state_dict: | |
continue | |
model_key = checkpoint_key | |
if remove_prefix_from_model: | |
# The model key starts with `prefix` but `checkpoint_key` doesn't so we add it. | |
model_key = f"{prefix}.{checkpoint_key}" | |
elif add_prefix_to_model: | |
# The model key doesn't start with `prefix` but `checkpoint_key` does so we remove it. | |
model_key = ".".join(checkpoint_key.split(".")[1:]) | |
if ( | |
model_key in model_state_dict | |
and state_dict[checkpoint_key].shape != model_state_dict[model_key].shape | |
): | |
if ( | |
state_dict[checkpoint_key].shape[-1] == 1 | |
and state_dict[checkpoint_key].numel() * 2 == model_state_dict[model_key].numel() | |
): | |
# This skips size mismatches for 4-bit weights. Two 4-bit values share an 8-bit container, causing size differences. | |
# Without matching with module type or paramter type it seems like a practical way to detect valid 4bit weights. | |
pass | |
else: | |
mismatched_keys.append( | |
(checkpoint_key, state_dict[checkpoint_key].shape, model_state_dict[model_key].shape) | |
) | |
del state_dict[checkpoint_key] | |
return mismatched_keys | |
if resolved_archive_file is not None: | |
folder = os.path.sep.join(resolved_archive_file[0].split(os.path.sep)[:-1]) | |
else: | |
folder = None | |
if device_map is not None and is_safetensors: | |
param_device_map = expand_device_map(device_map, original_loaded_keys, start_prefix) | |
str_dtype = str(dtype).replace("torch.", "") if dtype is not None else "float32" | |
if sharded_metadata is None: | |
archive_file = ( | |
resolved_archive_file[0] | |
if isinstance(resolved_archive_file, (list, tuple)) | |
else resolved_archive_file | |
) | |
weight_map = {p: archive_file for p in original_loaded_keys} | |
else: | |
weight_map = {p: os.path.join(folder, f) for p, f in sharded_metadata["weight_map"].items()} | |
offload_index = { | |
p[len(start_prefix) :]: {"safetensors_file": f, "weight_name": p, "dtype": str_dtype} | |
for p, f in weight_map.items() | |
if p.startswith(start_prefix) and param_device_map[p[len(start_prefix) :]] == "disk" | |
} | |
if state_dict is not None: | |
# Whole checkpoint | |
mismatched_keys = _find_mismatched_keys( | |
state_dict, | |
model_state_dict, | |
original_loaded_keys, | |
add_prefix_to_model, | |
remove_prefix_from_model, | |
ignore_mismatched_sizes, | |
) | |
error_msgs = _load_state_dict_into_model(model_to_load, state_dict, start_prefix) | |
offload_index = None | |
else: | |
# Sharded checkpoint or whole but low_cpu_mem_usage==True | |
# This should always be a list but, just to be sure. | |
if not isinstance(resolved_archive_file, list): | |
resolved_archive_file = [resolved_archive_file] | |
error_msgs = [] | |
mismatched_keys = [] | |
if not is_safetensors: | |
offload_index = {} if device_map is not None and "disk" in device_map.values() else None | |
if offload_state_dict: | |
state_dict_folder = tempfile.mkdtemp() | |
state_dict_index = {} | |
else: | |
state_dict_folder = None | |
state_dict_index = None | |
if is_sharded_safetensors: | |
disk_only_shard_files = get_disk_only_shard_files( | |
device_map, sharded_metadata=sharded_metadata, start_prefix=start_prefix | |
) | |
disk_only_shard_files = [os.path.join(folder, f) for f in disk_only_shard_files] | |
else: | |
disk_only_shard_files = [] | |
if len(resolved_archive_file) > 1: | |
resolved_archive_file = logging.tqdm(resolved_archive_file, desc="Loading checkpoint shards") | |
for shard_file in resolved_archive_file: | |
# Skip the load for shards that only contain disk-offloaded weights when using safetensors for the offload. | |
if shard_file in disk_only_shard_files: | |
continue | |
state_dict = load_state_dict(shard_file, is_quantized=is_quantized) | |
# Mistmatched keys contains tuples key/shape1/shape2 of weights in the checkpoint that have a shape not | |
# matching the weights in the model. | |
mismatched_keys += _find_mismatched_keys( | |
state_dict, | |
model_state_dict, | |
original_loaded_keys, | |
add_prefix_to_model, | |
remove_prefix_from_model, | |
ignore_mismatched_sizes, | |
) | |
if low_cpu_mem_usage: | |
if is_fsdp_enabled() and not is_local_dist_rank_0() and not is_quantized: | |
for key, param in model_to_load.state_dict().items(): | |
if param.device == torch.device("meta"): | |
set_module_tensor_to_device( | |
model_to_load, key, "cpu", torch.empty(*param.size(), dtype=dtype) | |
) | |
else: | |
new_error_msgs, offload_index, state_dict_index = _load_state_dict_into_meta_model( | |
model_to_load, | |
state_dict, | |
loaded_keys, | |
start_prefix, | |
expected_keys, | |
device_map=device_map, | |
offload_folder=offload_folder, | |
offload_index=offload_index, | |
state_dict_folder=state_dict_folder, | |
state_dict_index=state_dict_index, | |
dtype=dtype, | |
hf_quantizer=hf_quantizer, | |
is_safetensors=is_safetensors, | |
keep_in_fp32_modules=keep_in_fp32_modules, | |
unexpected_keys=unexpected_keys, | |
) | |
error_msgs += new_error_msgs | |
else: | |
error_msgs += _load_state_dict_into_model(model_to_load, state_dict, start_prefix) | |
# force memory release | |
del state_dict | |
gc.collect() | |
if offload_index is not None and len(offload_index) > 0: | |
if model != model_to_load: | |
# We need to add the prefix of the base model | |
prefix = cls.base_model_prefix | |
if not is_safetensors: | |
for weight_name in offload_index: | |
shutil.move( | |
os.path.join(offload_folder, f"{weight_name}.dat"), | |
os.path.join(offload_folder, f"{prefix}.{weight_name}.dat"), | |
) | |
offload_index = {f"{prefix}.{key}": value for key, value in offload_index.items()} | |
if not is_safetensors: | |
save_offload_index(offload_index, offload_folder) | |
offload_index = None | |
if offload_state_dict: | |
# Load back temporarily offloaded state dict | |
load_offloaded_weights(model_to_load, state_dict_index, state_dict_folder) | |
shutil.rmtree(state_dict_folder) | |
if len(error_msgs) > 0: | |
error_msg = "\n\t".join(error_msgs) | |
if "size mismatch" in error_msg: | |
error_msg += ( | |
"\n\tYou may consider adding `ignore_mismatched_sizes=True` in the model `from_pretrained` method." | |
) | |
raise RuntimeError(f"Error(s) in loading state_dict for {model.__class__.__name__}:\n\t{error_msg}") | |
if len(unexpected_keys) > 0: | |
archs = [] if model.config.architectures is None else model.config.architectures | |
warner = logger.warning if model.__class__.__name__ in archs else logger.info | |
warner( | |
f"Some weights of the model checkpoint at {pretrained_model_name_or_path} were not used when" | |
f" initializing {model.__class__.__name__}: {unexpected_keys}\n- This IS expected if you are" | |
f" initializing {model.__class__.__name__} from the checkpoint of a model trained on another task or" | |
" with another architecture (e.g. initializing a BertForSequenceClassification model from a" | |
" BertForPreTraining model).\n- This IS NOT expected if you are initializing" | |
f" {model.__class__.__name__} from the checkpoint of a model that you expect to be exactly identical" | |
" (initializing a BertForSequenceClassification model from a BertForSequenceClassification model)." | |
) | |
else: | |
logger.info(f"All model checkpoint weights were used when initializing {model.__class__.__name__}.\n") | |
if len(missing_keys) > 0: | |
logger.warning( | |
f"Some weights of {model.__class__.__name__} were not initialized from the model checkpoint at" | |
f" {pretrained_model_name_or_path} and are newly initialized: {missing_keys}\nYou should probably" | |
" TRAIN this model on a down-stream task to be able to use it for predictions and inference." | |
) | |
elif len(mismatched_keys) == 0: | |
logger.info( | |
f"All the weights of {model.__class__.__name__} were initialized from the model checkpoint at" | |
f" {pretrained_model_name_or_path}.\nIf your task is similar to the task the model of the checkpoint" | |
f" was trained on, you can already use {model.__class__.__name__} for predictions without further" | |
" training." | |
) | |
if len(mismatched_keys) > 0: | |
mismatched_warning = "\n".join( | |
[ | |
f"- {key}: found shape {shape1} in the checkpoint and {shape2} in the model instantiated" | |
for key, shape1, shape2 in mismatched_keys | |
] | |
) | |
logger.warning( | |
f"Some weights of {model.__class__.__name__} were not initialized from the model checkpoint at" | |
f" {pretrained_model_name_or_path} and are newly initialized because the shapes did not" | |
f" match:\n{mismatched_warning}\nYou should probably TRAIN this model on a down-stream task to be able" | |
" to use it for predictions and inference." | |
) | |
return model, missing_keys, unexpected_keys, mismatched_keys, offload_index, error_msgs | |
def retrieve_modules_from_names(self, names, add_prefix=False, remove_prefix=False): | |
module_keys = {".".join(key.split(".")[:-1]) for key in names} | |
# torch.nn.ParameterList is a special case where two parameter keywords | |
# are appended to the module name, *e.g.* bert.special_embeddings.0 | |
module_keys = module_keys.union( | |
{".".join(key.split(".")[:-2]) for key in names if len(key) > 0 and key[-1].isdigit()} | |
) | |
retrieved_modules = [] | |
# retrieve all modules that has at least one missing weight name | |
for name, module in self.named_modules(): | |
if remove_prefix: | |
_prefix = f"{self.base_model_prefix}." | |
name = name[len(_prefix) :] if name.startswith(_prefix) else name | |
elif add_prefix: | |
name = ".".join([self.base_model_prefix, name]) if len(name) > 0 else self.base_model_prefix | |
if name in module_keys: | |
retrieved_modules.append(module) | |
return retrieved_modules | |
def _load_pretrained_model_low_mem( | |
model, loaded_state_dict_keys, resolved_archive_file, start_prefix="", hf_quantizer=None | |
): | |
""" | |
This is an experimental function that loads the model using ~1.x model size CPU memory | |
Before you call it do: | |
1. save which state_dict keys are available | |
2. drop state_dict before model is created, since the latter takes 1x model size memory | |
Here then we continue: | |
3. switch to the meta device all params/buffers that are going to be replaced from the loaded state_dict | |
4. load state_dict 2nd time | |
5. replace the params/buffers from the state_dict | |
Currently, it doesn't handle missing_keys, unexpected_keys, mismatched_keys. It can't handle deepspeed. To | |
handle bitsandbytes, needs non-empty hf_quantizer argument. | |
""" | |
_move_model_to_meta(model, loaded_state_dict_keys, start_prefix) | |
state_dict = load_state_dict(resolved_archive_file) | |
expected_keys = loaded_state_dict_keys # plug for missing expected_keys. TODO: replace with proper keys | |
error_msgs = _load_state_dict_into_meta_model( | |
model, | |
state_dict, | |
loaded_state_dict_keys, | |
start_prefix, | |
expected_keys=expected_keys, | |
hf_quantizer=hf_quantizer, | |
) | |
return error_msgs | |
def register_for_auto_class(cls, auto_class="AutoModel"): | |
""" | |
Register this class with a given auto class. This should only be used for custom models as the ones in the | |
library are already mapped with an auto class. | |
<Tip warning={true}> | |
This API is experimental and may have some slight breaking changes in the next releases. | |
</Tip> | |
Args: | |
auto_class (`str` or `type`, *optional*, defaults to `"AutoModel"`): | |
The auto class to register this new model with. | |
""" | |
if not isinstance(auto_class, str): | |
auto_class = auto_class.__name__ | |
import transformers.models.auto as auto_module | |
if not hasattr(auto_module, auto_class): | |
raise ValueError(f"{auto_class} is not a valid auto class.") | |
cls._auto_class = auto_class | |
def to_bettertransformer(self) -> "PreTrainedModel": | |
""" | |
Converts the model to use [PyTorch's native attention | |
implementation](https://pytorch.org/docs/stable/generated/torch.nn.MultiheadAttention.html), integrated to | |
Transformers through [Optimum library](https://huggingface.co/docs/optimum/bettertransformer/overview). Only a | |
subset of all Transformers models are supported. | |
PyTorch's attention fastpath allows to speed up inference through kernel fusions and the use of [nested | |
tensors](https://pytorch.org/docs/stable/nested.html). Detailed benchmarks can be found in [this blog | |
post](https://medium.com/pytorch/bettertransformer-out-of-the-box-performance-for-huggingface-transformers-3fbe27d50ab2). | |
Returns: | |
[`PreTrainedModel`]: The model converted to BetterTransformer. | |
""" | |
if not is_optimum_available(): | |
raise ImportError("The package `optimum` is required to use Better Transformer.") | |
from optimum.version import __version__ as optimum_version | |
if version.parse(optimum_version) < version.parse("1.7.0"): | |
raise ImportError( | |
f"Please install optimum>=1.7.0 to use Better Transformer. The version {optimum_version} was found." | |
) | |
from optimum.bettertransformer import BetterTransformer | |
return BetterTransformer.transform(self) | |
def reverse_bettertransformer(self): | |
""" | |
Reverts the transformation from [`~PreTrainedModel.to_bettertransformer`] so that the original modeling is | |
used, for example in order to save the model. | |
Returns: | |
[`PreTrainedModel`]: The model converted back to the original modeling. | |
""" | |
if not is_optimum_available(): | |
raise ImportError("The package `optimum` is required to use Better Transformer.") | |
from optimum.version import __version__ as optimum_version | |
if version.parse(optimum_version) < version.parse("1.7.0"): | |
raise ImportError( | |
f"Please install optimum>=1.7.0 to use Better Transformer. The version {optimum_version} was found." | |
) | |
from optimum.bettertransformer import BetterTransformer | |
return BetterTransformer.reverse(self) | |
def warn_if_padding_and_no_attention_mask(self, input_ids, attention_mask): | |
""" | |
Shows a one-time warning if the input_ids appear to contain padding and no attention mask was given. | |
""" | |
# Skip the check during tracing. | |
if is_torch_fx_proxy(input_ids) or torch.jit.is_tracing() or is_torchdynamo_compiling(): | |
return | |
if (attention_mask is not None) or (self.config.pad_token_id is None): | |
return | |
# Check only the first and last input IDs to reduce overhead. | |
if self.config.pad_token_id in input_ids[:, [-1, 0]]: | |
warn_string = ( | |
"We strongly recommend passing in an `attention_mask` since your input_ids may be padded. See " | |
"https://huggingface.co/docs/transformers/troubleshooting" | |
"#incorrect-output-when-padding-tokens-arent-masked." | |
) | |
# If the pad token is equal to either BOS, EOS, or SEP, we do not know whether the user should use an | |
# attention_mask or not. In this case, we should still show a warning because this is a rare case. | |
if ( | |
(self.config.bos_token_id is not None and self.config.bos_token_id == self.config.pad_token_id) | |
or (self.config.eos_token_id is not None and self.config.eos_token_id == self.config.pad_token_id) | |
or (self.config.sep_token_id is not None and self.config.sep_token_id == self.config.pad_token_id) | |
): | |
warn_string += ( | |
f"\nYou may ignore this warning if your `pad_token_id` ({self.config.pad_token_id}) is identical " | |
f"to the `bos_token_id` ({self.config.bos_token_id}), `eos_token_id` ({self.config.eos_token_id}), " | |
f"or the `sep_token_id` ({self.config.sep_token_id}), and your input is not padded." | |
) | |
logger.warning_once(warn_string) | |
def _is_quantized_training_enabled(self): | |
warnings.warn( | |
"`_is_quantized_training_enabled` is going to be deprecated in transformers 4.39.0. Please use `model.hf_quantizer.is_trainable` instead", | |
FutureWarning, | |
) | |
if not hasattr(self, "hf_quantizer"): | |
return False | |
return self.hf_quantizer.is_trainable | |
PreTrainedModel.push_to_hub = copy_func(PreTrainedModel.push_to_hub) | |
if PreTrainedModel.push_to_hub.__doc__ is not None: | |
PreTrainedModel.push_to_hub.__doc__ = PreTrainedModel.push_to_hub.__doc__.format( | |
object="model", object_class="AutoModel", object_files="model file" | |
) | |
class PoolerStartLogits(nn.Module): | |
""" | |
Compute SQuAD start logits from sequence hidden states. | |
Args: | |
config ([`PretrainedConfig`]): | |
The config used by the model, will be used to grab the `hidden_size` of the model. | |
""" | |
def __init__(self, config: PretrainedConfig): | |
super().__init__() | |
self.dense = nn.Linear(config.hidden_size, 1) | |
def forward( | |
self, hidden_states: torch.FloatTensor, p_mask: Optional[torch.FloatTensor] = None | |
) -> torch.FloatTensor: | |
""" | |
Args: | |
hidden_states (`torch.FloatTensor` of shape `(batch_size, seq_len, hidden_size)`): | |
The final hidden states of the model. | |
p_mask (`torch.FloatTensor` of shape `(batch_size, seq_len)`, *optional*): | |
Mask for tokens at invalid position, such as query and special symbols (PAD, SEP, CLS). 1.0 means token | |
should be masked. | |
Returns: | |
`torch.FloatTensor`: The start logits for SQuAD. | |
""" | |
x = self.dense(hidden_states).squeeze(-1) | |
if p_mask is not None: | |
if get_parameter_dtype(self) == torch.float16: | |
x = x * (1 - p_mask) - 65500 * p_mask | |
else: | |
x = x * (1 - p_mask) - 1e30 * p_mask | |
return x | |
class PoolerEndLogits(nn.Module): | |
""" | |
Compute SQuAD end logits from sequence hidden states. | |
Args: | |
config ([`PretrainedConfig`]): | |
The config used by the model, will be used to grab the `hidden_size` of the model and the `layer_norm_eps` | |
to use. | |
""" | |
def __init__(self, config: PretrainedConfig): | |
super().__init__() | |
self.dense_0 = nn.Linear(config.hidden_size * 2, config.hidden_size) | |
self.activation = nn.Tanh() | |
self.LayerNorm = nn.LayerNorm(config.hidden_size, eps=config.layer_norm_eps) | |
self.dense_1 = nn.Linear(config.hidden_size, 1) | |
def forward( | |
self, | |
hidden_states: torch.FloatTensor, | |
start_states: Optional[torch.FloatTensor] = None, | |
start_positions: Optional[torch.LongTensor] = None, | |
p_mask: Optional[torch.FloatTensor] = None, | |
) -> torch.FloatTensor: | |
""" | |
Args: | |
hidden_states (`torch.FloatTensor` of shape `(batch_size, seq_len, hidden_size)`): | |
The final hidden states of the model. | |
start_states (`torch.FloatTensor` of shape `(batch_size, seq_len, hidden_size)`, *optional*): | |
The hidden states of the first tokens for the labeled span. | |
start_positions (`torch.LongTensor` of shape `(batch_size,)`, *optional*): | |
The position of the first token for the labeled span. | |
p_mask (`torch.FloatTensor` of shape `(batch_size, seq_len)`, *optional*): | |
Mask for tokens at invalid position, such as query and special symbols (PAD, SEP, CLS). 1.0 means token | |
should be masked. | |
<Tip> | |
One of `start_states` or `start_positions` should be not `None`. If both are set, `start_positions` overrides | |
`start_states`. | |
</Tip> | |
Returns: | |
`torch.FloatTensor`: The end logits for SQuAD. | |
""" | |
assert ( | |
start_states is not None or start_positions is not None | |
), "One of start_states, start_positions should be not None" | |
if start_positions is not None: | |
slen, hsz = hidden_states.shape[-2:] | |
start_positions = start_positions[:, None, None].expand(-1, -1, hsz) # shape (bsz, 1, hsz) | |
start_states = hidden_states.gather(-2, start_positions) # shape (bsz, 1, hsz) | |
start_states = start_states.expand(-1, slen, -1) # shape (bsz, slen, hsz) | |
x = self.dense_0(torch.cat([hidden_states, start_states], dim=-1)) | |
x = self.activation(x) | |
x = self.LayerNorm(x) | |
x = self.dense_1(x).squeeze(-1) | |
if p_mask is not None: | |
if get_parameter_dtype(self) == torch.float16: | |
x = x * (1 - p_mask) - 65500 * p_mask | |
else: | |
x = x * (1 - p_mask) - 1e30 * p_mask | |
return x | |
class PoolerAnswerClass(nn.Module): | |
""" | |
Compute SQuAD 2.0 answer class from classification and start tokens hidden states. | |
Args: | |
config ([`PretrainedConfig`]): | |
The config used by the model, will be used to grab the `hidden_size` of the model. | |
""" | |
def __init__(self, config): | |
super().__init__() | |
self.dense_0 = nn.Linear(config.hidden_size * 2, config.hidden_size) | |
self.activation = nn.Tanh() | |
self.dense_1 = nn.Linear(config.hidden_size, 1, bias=False) | |
def forward( | |
self, | |
hidden_states: torch.FloatTensor, | |
start_states: Optional[torch.FloatTensor] = None, | |
start_positions: Optional[torch.LongTensor] = None, | |
cls_index: Optional[torch.LongTensor] = None, | |
) -> torch.FloatTensor: | |
""" | |
Args: | |
hidden_states (`torch.FloatTensor` of shape `(batch_size, seq_len, hidden_size)`): | |
The final hidden states of the model. | |
start_states (`torch.FloatTensor` of shape `(batch_size, seq_len, hidden_size)`, *optional*): | |
The hidden states of the first tokens for the labeled span. | |
start_positions (`torch.LongTensor` of shape `(batch_size,)`, *optional*): | |
The position of the first token for the labeled span. | |
cls_index (`torch.LongTensor` of shape `(batch_size,)`, *optional*): | |
Position of the CLS token for each sentence in the batch. If `None`, takes the last token. | |
<Tip> | |
One of `start_states` or `start_positions` should be not `None`. If both are set, `start_positions` overrides | |
`start_states`. | |
</Tip> | |
Returns: | |
`torch.FloatTensor`: The SQuAD 2.0 answer class. | |
""" | |
# No dependency on end_feature so that we can obtain one single `cls_logits` for each sample. | |
hsz = hidden_states.shape[-1] | |
assert ( | |
start_states is not None or start_positions is not None | |
), "One of start_states, start_positions should be not None" | |
if start_positions is not None: | |
start_positions = start_positions[:, None, None].expand(-1, -1, hsz) # shape (bsz, 1, hsz) | |
start_states = hidden_states.gather(-2, start_positions).squeeze(-2) # shape (bsz, hsz) | |
if cls_index is not None: | |
cls_index = cls_index[:, None, None].expand(-1, -1, hsz) # shape (bsz, 1, hsz) | |
cls_token_state = hidden_states.gather(-2, cls_index).squeeze(-2) # shape (bsz, hsz) | |
else: | |
cls_token_state = hidden_states[:, -1, :] # shape (bsz, hsz) | |
x = self.dense_0(torch.cat([start_states, cls_token_state], dim=-1)) | |
x = self.activation(x) | |
x = self.dense_1(x).squeeze(-1) | |
return x | |
class SquadHeadOutput(ModelOutput): | |
""" | |
Base class for outputs of question answering models using a [`~modeling_utils.SQuADHead`]. | |
Args: | |
loss (`torch.FloatTensor` of shape `(1,)`, *optional*, returned if both `start_positions` and `end_positions` are provided): | |
Classification loss as the sum of start token, end token (and is_impossible if provided) classification | |
losses. | |
start_top_log_probs (`torch.FloatTensor` of shape `(batch_size, config.start_n_top)`, *optional*, returned if `start_positions` or `end_positions` is not provided): | |
Log probabilities for the top config.start_n_top start token possibilities (beam-search). | |
start_top_index (`torch.LongTensor` of shape `(batch_size, config.start_n_top)`, *optional*, returned if `start_positions` or `end_positions` is not provided): | |
Indices for the top config.start_n_top start token possibilities (beam-search). | |
end_top_log_probs (`torch.FloatTensor` of shape `(batch_size, config.start_n_top * config.end_n_top)`, *optional*, returned if `start_positions` or `end_positions` is not provided): | |
Log probabilities for the top `config.start_n_top * config.end_n_top` end token possibilities | |
(beam-search). | |
end_top_index (`torch.LongTensor` of shape `(batch_size, config.start_n_top * config.end_n_top)`, *optional*, returned if `start_positions` or `end_positions` is not provided): | |
Indices for the top `config.start_n_top * config.end_n_top` end token possibilities (beam-search). | |
cls_logits (`torch.FloatTensor` of shape `(batch_size,)`, *optional*, returned if `start_positions` or `end_positions` is not provided): | |
Log probabilities for the `is_impossible` label of the answers. | |
""" | |
loss: Optional[torch.FloatTensor] = None | |
start_top_log_probs: Optional[torch.FloatTensor] = None | |
start_top_index: Optional[torch.LongTensor] = None | |
end_top_log_probs: Optional[torch.FloatTensor] = None | |
end_top_index: Optional[torch.LongTensor] = None | |
cls_logits: Optional[torch.FloatTensor] = None | |
class SQuADHead(nn.Module): | |
r""" | |
A SQuAD head inspired by XLNet. | |
Args: | |
config ([`PretrainedConfig`]): | |
The config used by the model, will be used to grab the `hidden_size` of the model and the `layer_norm_eps` | |
to use. | |
""" | |
def __init__(self, config): | |
super().__init__() | |
self.start_n_top = config.start_n_top | |
self.end_n_top = config.end_n_top | |
self.start_logits = PoolerStartLogits(config) | |
self.end_logits = PoolerEndLogits(config) | |
self.answer_class = PoolerAnswerClass(config) | |
def forward( | |
self, | |
hidden_states: torch.FloatTensor, | |
start_positions: Optional[torch.LongTensor] = None, | |
end_positions: Optional[torch.LongTensor] = None, | |
cls_index: Optional[torch.LongTensor] = None, | |
is_impossible: Optional[torch.LongTensor] = None, | |
p_mask: Optional[torch.FloatTensor] = None, | |
return_dict: bool = False, | |
) -> Union[SquadHeadOutput, Tuple[torch.FloatTensor]]: | |
""" | |
Args: | |
hidden_states (`torch.FloatTensor` of shape `(batch_size, seq_len, hidden_size)`): | |
Final hidden states of the model on the sequence tokens. | |
start_positions (`torch.LongTensor` of shape `(batch_size,)`, *optional*): | |
Positions of the first token for the labeled span. | |
end_positions (`torch.LongTensor` of shape `(batch_size,)`, *optional*): | |
Positions of the last token for the labeled span. | |
cls_index (`torch.LongTensor` of shape `(batch_size,)`, *optional*): | |
Position of the CLS token for each sentence in the batch. If `None`, takes the last token. | |
is_impossible (`torch.LongTensor` of shape `(batch_size,)`, *optional*): | |
Whether the question has a possible answer in the paragraph or not. | |
p_mask (`torch.FloatTensor` of shape `(batch_size, seq_len)`, *optional*): | |
Mask for tokens at invalid position, such as query and special symbols (PAD, SEP, CLS). 1.0 means token | |
should be masked. | |
return_dict (`bool`, *optional*, defaults to `False`): | |
Whether or not to return a [`~utils.ModelOutput`] instead of a plain tuple. | |
Returns: | |
""" | |
start_logits = self.start_logits(hidden_states, p_mask=p_mask) | |
if start_positions is not None and end_positions is not None: | |
# If we are on multi-GPU, let's remove the dimension added by batch splitting | |
for x in (start_positions, end_positions, cls_index, is_impossible): | |
if x is not None and x.dim() > 1: | |
x.squeeze_(-1) | |
# during training, compute the end logits based on the ground truth of the start position | |
end_logits = self.end_logits(hidden_states, start_positions=start_positions, p_mask=p_mask) | |
loss_fct = CrossEntropyLoss() | |
start_loss = loss_fct(start_logits, start_positions) | |
end_loss = loss_fct(end_logits, end_positions) | |
total_loss = (start_loss + end_loss) / 2 | |
if cls_index is not None and is_impossible is not None: | |
# Predict answerability from the representation of CLS and START | |
cls_logits = self.answer_class(hidden_states, start_positions=start_positions, cls_index=cls_index) | |
loss_fct_cls = nn.BCEWithLogitsLoss() | |
cls_loss = loss_fct_cls(cls_logits, is_impossible) | |
# note(zhiliny): by default multiply the loss by 0.5 so that the scale is comparable to start_loss and end_loss | |
total_loss += cls_loss * 0.5 | |
return SquadHeadOutput(loss=total_loss) if return_dict else (total_loss,) | |
else: | |
# during inference, compute the end logits based on beam search | |
bsz, slen, hsz = hidden_states.size() | |
start_log_probs = nn.functional.softmax(start_logits, dim=-1) # shape (bsz, slen) | |
start_top_log_probs, start_top_index = torch.topk( | |
start_log_probs, self.start_n_top, dim=-1 | |
) # shape (bsz, start_n_top) | |
start_top_index_exp = start_top_index.unsqueeze(-1).expand(-1, -1, hsz) # shape (bsz, start_n_top, hsz) | |
start_states = torch.gather(hidden_states, -2, start_top_index_exp) # shape (bsz, start_n_top, hsz) | |
start_states = start_states.unsqueeze(1).expand(-1, slen, -1, -1) # shape (bsz, slen, start_n_top, hsz) | |
hidden_states_expanded = hidden_states.unsqueeze(2).expand_as( | |
start_states | |
) # shape (bsz, slen, start_n_top, hsz) | |
p_mask = p_mask.unsqueeze(-1) if p_mask is not None else None | |
end_logits = self.end_logits(hidden_states_expanded, start_states=start_states, p_mask=p_mask) | |
end_log_probs = nn.functional.softmax(end_logits, dim=1) # shape (bsz, slen, start_n_top) | |
end_top_log_probs, end_top_index = torch.topk( | |
end_log_probs, self.end_n_top, dim=1 | |
) # shape (bsz, end_n_top, start_n_top) | |
end_top_log_probs = end_top_log_probs.view(-1, self.start_n_top * self.end_n_top) | |
end_top_index = end_top_index.view(-1, self.start_n_top * self.end_n_top) | |
start_states = torch.einsum("blh,bl->bh", hidden_states, start_log_probs) | |
cls_logits = self.answer_class(hidden_states, start_states=start_states, cls_index=cls_index) | |
if not return_dict: | |
return (start_top_log_probs, start_top_index, end_top_log_probs, end_top_index, cls_logits) | |
else: | |
return SquadHeadOutput( | |
start_top_log_probs=start_top_log_probs, | |
start_top_index=start_top_index, | |
end_top_log_probs=end_top_log_probs, | |
end_top_index=end_top_index, | |
cls_logits=cls_logits, | |
) | |
class SequenceSummary(nn.Module): | |
r""" | |
Compute a single vector summary of a sequence hidden states. | |
Args: | |
config ([`PretrainedConfig`]): | |
The config used by the model. Relevant arguments in the config class of the model are (refer to the actual | |
config class of your model for the default values it uses): | |
- **summary_type** (`str`) -- The method to use to make this summary. Accepted values are: | |
- `"last"` -- Take the last token hidden state (like XLNet) | |
- `"first"` -- Take the first token hidden state (like Bert) | |
- `"mean"` -- Take the mean of all tokens hidden states | |
- `"cls_index"` -- Supply a Tensor of classification token position (GPT/GPT-2) | |
- `"attn"` -- Not implemented now, use multi-head attention | |
- **summary_use_proj** (`bool`) -- Add a projection after the vector extraction. | |
- **summary_proj_to_labels** (`bool`) -- If `True`, the projection outputs to `config.num_labels` classes | |
(otherwise to `config.hidden_size`). | |
- **summary_activation** (`Optional[str]`) -- Set to `"tanh"` to add a tanh activation to the output, | |
another string or `None` will add no activation. | |
- **summary_first_dropout** (`float`) -- Optional dropout probability before the projection and activation. | |
- **summary_last_dropout** (`float`)-- Optional dropout probability after the projection and activation. | |
""" | |
def __init__(self, config: PretrainedConfig): | |
super().__init__() | |
self.summary_type = getattr(config, "summary_type", "last") | |
if self.summary_type == "attn": | |
# We should use a standard multi-head attention module with absolute positional embedding for that. | |
# Cf. https://github.com/zihangdai/xlnet/blob/master/modeling.py#L253-L276 | |
# We can probably just use the multi-head attention module of PyTorch >=1.1.0 | |
raise NotImplementedError | |
self.summary = Identity() | |
if hasattr(config, "summary_use_proj") and config.summary_use_proj: | |
if hasattr(config, "summary_proj_to_labels") and config.summary_proj_to_labels and config.num_labels > 0: | |
num_classes = config.num_labels | |
else: | |
num_classes = config.hidden_size | |
self.summary = nn.Linear(config.hidden_size, num_classes) | |
activation_string = getattr(config, "summary_activation", None) | |
self.activation: Callable = get_activation(activation_string) if activation_string else Identity() | |
self.first_dropout = Identity() | |
if hasattr(config, "summary_first_dropout") and config.summary_first_dropout > 0: | |
self.first_dropout = nn.Dropout(config.summary_first_dropout) | |
self.last_dropout = Identity() | |
if hasattr(config, "summary_last_dropout") and config.summary_last_dropout > 0: | |
self.last_dropout = nn.Dropout(config.summary_last_dropout) | |
def forward( | |
self, hidden_states: torch.FloatTensor, cls_index: Optional[torch.LongTensor] = None | |
) -> torch.FloatTensor: | |
""" | |
Compute a single vector summary of a sequence hidden states. | |
Args: | |
hidden_states (`torch.FloatTensor` of shape `[batch_size, seq_len, hidden_size]`): | |
The hidden states of the last layer. | |
cls_index (`torch.LongTensor` of shape `[batch_size]` or `[batch_size, ...]` where ... are optional leading dimensions of `hidden_states`, *optional*): | |
Used if `summary_type == "cls_index"` and takes the last token of the sequence as classification token. | |
Returns: | |
`torch.FloatTensor`: The summary of the sequence hidden states. | |
""" | |
if self.summary_type == "last": | |
output = hidden_states[:, -1] | |
elif self.summary_type == "first": | |
output = hidden_states[:, 0] | |
elif self.summary_type == "mean": | |
output = hidden_states.mean(dim=1) | |
elif self.summary_type == "cls_index": | |
if cls_index is None: | |
cls_index = torch.full_like( | |
hidden_states[..., :1, :], | |
hidden_states.shape[-2] - 1, | |
dtype=torch.long, | |
) | |
else: | |
cls_index = cls_index.unsqueeze(-1).unsqueeze(-1) | |
cls_index = cls_index.expand((-1,) * (cls_index.dim() - 1) + (hidden_states.size(-1),)) | |
# shape of cls_index: (bsz, XX, 1, hidden_size) where XX are optional leading dim of hidden_states | |
output = hidden_states.gather(-2, cls_index).squeeze(-2) # shape (bsz, XX, hidden_size) | |
elif self.summary_type == "attn": | |
raise NotImplementedError | |
output = self.first_dropout(output) | |
output = self.summary(output) | |
output = self.activation(output) | |
output = self.last_dropout(output) | |
return output | |
def unwrap_model(model: nn.Module, recursive: bool = False) -> nn.Module: | |
""" | |
Recursively unwraps a model from potential containers (as used in distributed training). | |
Args: | |
model (`torch.nn.Module`): The model to unwrap. | |
recursive (`bool`, *optional*, defaults to `False`): | |
Whether to recursively extract all cases of `module.module` from `model` as well as unwrap child sublayers | |
recursively, not just the top-level distributed containers. | |
""" | |
# Use accelerate implementation if available (should always be the case when using torch) | |
# This is for pytorch, as we also have to handle things like dynamo | |
if is_accelerate_available(): | |
kwargs = {} | |
if recursive: | |
if not is_accelerate_available("0.29.0"): | |
raise RuntimeError( | |
"Setting `recursive=True` to `unwrap_model` requires `accelerate` v0.29.0. Please upgrade your version of accelerate" | |
) | |
else: | |
kwargs["recursive"] = recursive | |
return extract_model_from_parallel(model, **kwargs) | |
else: | |
# since there could be multiple levels of wrapping, unwrap recursively | |
if hasattr(model, "module"): | |
return unwrap_model(model.module) | |
else: | |
return model | |
def expand_device_map(device_map, param_names, start_prefix): | |
""" | |
Expand a device map to return the correspondance parameter name to device. | |
""" | |
new_device_map = {} | |
param_names = [p[len(start_prefix) :] for p in param_names if p.startswith(start_prefix)] | |
for module, device in device_map.items(): | |
new_device_map.update( | |
{p: device for p in param_names if p == module or p.startswith(f"{module}.") or module == ""} | |
) | |
return new_device_map | |
def get_disk_only_shard_files(device_map, sharded_metadata, start_prefix): | |
""" | |
Returns the list of shard files containing only weights offloaded to disk. | |
""" | |
weight_map = { | |
p[len(start_prefix) :]: v for p, v in sharded_metadata["weight_map"].items() if p.startswith(start_prefix) | |
} | |
files_content = collections.defaultdict(list) | |
for weight_name, filename in weight_map.items(): | |
while len(weight_name) > 0 and weight_name not in device_map: | |
weight_name = ".".join(weight_name.split(".")[:-1]) | |
files_content[filename].append(device_map[weight_name]) | |
return [fname for fname, devices in files_content.items() if set(devices) == {"disk"}] | |