4-bit QLoRA via bitsandbytes (4-bit base model + LoRA) (#23479)

* Added lion and paged optimizers and made original tests pass.

* Added tests for paged and lion optimizers.

* Added and fixed optimizer tests.

* Style and quality checks.

* Initial draft. Some tests fail.

* Fixed dtype bug.

* Fixed bug caused by torch_dtype='auto'.

* All test green for 8-bit and 4-bit layers.

* Added fix for fp32 layer norms and bf16 compute in LLaMA.

* Initial draft. Some tests fail.

* Fixed dtype bug.

* Fixed bug caused by torch_dtype='auto'.

* All test green for 8-bit and 4-bit layers.

* Added lion and paged optimizers and made original tests pass.

* Added tests for paged and lion optimizers.

* Added and fixed optimizer tests.

* Style and quality checks.

* Fixing issues for PR #23479.

* Added fix for fp32 layer norms and bf16 compute in LLaMA.

* Reverted variable name change.

* Initial draft. Some tests fail.

* Fixed dtype bug.

* Fixed bug caused by torch_dtype='auto'.

* All test green for 8-bit and 4-bit layers.

* Added lion and paged optimizers and made original tests pass.

* Added tests for paged and lion optimizers.

* Added and fixed optimizer tests.

* Style and quality checks.

* Added missing tests.

* Fixup changes.

* Added fixup changes.

* Missed some variables to rename.

* revert trainer tests

* revert test trainer

* another revert

* fix tests and safety checkers

* protect import

* simplify a bit

* Update src/transformers/trainer.py

* few fixes

* add warning

* replace with `load_in_kbit = load_in_4bit or load_in_8bit`

* fix test

* fix tests

* this time fix tests

* safety checker

* add docs

* revert torch_dtype

* Apply suggestions from code review

Co-authored-by: Sylvain Gugger <35901082+sgugger@users.noreply.github.com>

* multiple fixes

* update docs

* version checks and multiple fixes

* replace `is_loaded_in_kbit`

* replace `load_in_kbit`

* change methods names

* better checks

* oops

* oops

* address final comments

---------

Co-authored-by: younesbelkada <younesbelkada@gmail.com>
Co-authored-by: Younes Belkada <49240599+younesbelkada@users.noreply.github.com>
Co-authored-by: Sylvain Gugger <35901082+sgugger@users.noreply.github.com>
This commit is contained in:
Tim Dettmers
2023-05-24 03:52:45 -07:00
committed by GitHub
parent 33687a3f61
commit 9d73b92269
10 changed files with 864 additions and 76 deletions

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# Testing mixed int8 quantization
![HFxbitsandbytes.png](https://s3.amazonaws.com/moonup/production/uploads/1660567705337-62441d1d9fdefb55a0b7d12c.png)
The following is the recipe on how to effectively debug `bitsandbytes` integration on Hugging Face `transformers`.
## Library requirements
+ `transformers>=4.22.0`
+ `accelerate>=0.12.0`
+ `bitsandbytes>=0.31.5`.
## Hardware requirements
The following instructions are tested with 2 NVIDIA-Tesla T4 GPUs. To run successfully `bitsandbytes` you would need a 8-bit core tensor supported GPU. Note that Turing, Ampere or newer architectures - e.g. T4, RTX20s RTX30s, A40-A100, A6000 should be supported.
## Virutal envs
```bash
conda create --name int8-testing python==3.8
pip install bitsandbytes>=0.31.5
pip install accelerate>=0.12.0
pip install transformers>=4.23.0
```
if `transformers>=4.23.0` is not released yet, then use:
```
pip install git+https://github.com/huggingface/transformers.git
```
## Troubleshooting
A list of common errors:
### Torch does not correctly do the operations on GPU
First check that:
```py
import torch
vec = torch.randn(1, 2, 3).to(0)
```
Works without any error. If not, install torch using `conda` like:
```bash
conda create --name int8-testing python==3.8
conda install pytorch torchvision torchaudio cudatoolkit=11.6 -c pytorch -c conda-forge
pip install bitsandbytes>=0.31.5
pip install accelerate>=0.12.0
pip install transformers>=4.23.0
```
For the latest pytorch instructions please see [this](https://pytorch.org/get-started/locally/)
and the snippet above should work.
### ` bitsandbytes operations are not supported under CPU!`
This happens when some Linear weights are set to the CPU when using `accelerate`. Please check carefully `model.hf_device_map` and make sure that there is no `Linear` module that is assigned to CPU. It is fine to have the last module (usually the Lm_head) set on CPU.
### `To use the type as a Parameter, please correct the detach() semantics defined by __torch_dispatch__() implementation.`
Use the latest version of `accelerate` with a command such as: `pip install -U accelerate` and the problem should be solved.
### `Parameter has no attribue .CB`
Same solution as above.
### `RuntimeError: CUDA error: an illegal memory access was encountered ... consider passing CUDA_LAUNCH_BLOCKING=1`
Run your script by pre-pending `CUDA_LAUNCH_BLOCKING=1` and you should observe an error as described in the next section.
### `CUDA illegal memory error: an illegal memory access at line...`:
Check the CUDA verisons with:
```
nvcc --version
```
and confirm it is the same version as the one detected by `bitsandbytes`. If not, run:
```
ls -l $CONDA_PREFIX/lib/libcudart.so
```
or
```
ls -l $LD_LIBRARY_PATH
```
Check if `libcudart.so` has a correct symlink that is set. Sometimes `nvcc` detects the correct CUDA version but `bitsandbytes` doesn't. You have to make sure that the symlink that is set for the file `libcudart.so` is redirected to the correct CUDA file.
Here is an example of a badly configured CUDA installation:
`nvcc --version` gives:
![Screenshot 2022-08-15 at 15.12.23.png](https://s3.amazonaws.com/moonup/production/uploads/1660569220888-62441d1d9fdefb55a0b7d12c.png)
which means that the detected CUDA version is 11.3 but `bitsandbytes` outputs:
![image.png](https://s3.amazonaws.com/moonup/production/uploads/1660569284243-62441d1d9fdefb55a0b7d12c.png)
First check:
```bash
echo $LD_LIBRARY_PATH
```
If this contains multiple paths separated by `:`. Then you have to make sure that the correct CUDA version is set. By doing:
```bash
ls -l $path/libcudart.so
```
On each path (`$path`) separated by `:`.
If not, simply run
```bash
ls -l $LD_LIBRARY_PATH/libcudart.so
```
and you can see
![Screenshot 2022-08-15 at 15.12.33.png](https://s3.amazonaws.com/moonup/production/uploads/1660569176504-62441d1d9fdefb55a0b7d12c.png)
If you see that the file is linked to the wrong CUDA version (here 10.2), find the correct location for `libcudart.so` (`find --name libcudart.so`) and replace the environment variable `LD_LIBRARY_PATH` with the one containing the correct `libcudart.so` file.

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# coding=utf-8
# Copyright 2022 The HuggingFace Team Inc.
#
# 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 clone 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 gc
import tempfile
import unittest
from packaging import version
from transformers import (
AutoModel,
AutoModelForCausalLM,
AutoModelForSeq2SeqLM,
AutoModelForSequenceClassification,
AutoTokenizer,
BitsAndBytesConfig,
pipeline,
)
from transformers.testing_utils import (
is_torch_available,
require_accelerate,
require_bitsandbytes,
require_torch,
require_torch_gpu,
require_torch_multi_gpu,
slow,
)
from transformers.utils.versions import importlib_metadata
if is_torch_available():
import torch
import torch.nn as nn
class LoRALayer(nn.Module):
"""Wraps a linear layer with LoRA-like adapter - Used for testing purposes only"""
def __init__(self, module: nn.Module, rank: int):
super().__init__()
self.module = module
self.adapter = nn.Sequential(
nn.Linear(module.in_features, rank, bias=False),
nn.Linear(rank, module.out_features, bias=False),
)
small_std = (2.0 / (5 * min(module.in_features, module.out_features))) ** 0.5
nn.init.normal_(self.adapter[0].weight, std=small_std)
nn.init.zeros_(self.adapter[1].weight)
self.adapter.to(module.weight.device)
def forward(self, input, *args, **kwargs):
return self.module(input, *args, **kwargs) + self.adapter(input)
@require_bitsandbytes
@require_accelerate
@require_torch
@require_torch_gpu
@slow
class Base4bitTest(unittest.TestCase):
# We keep the constants inside the init function and model loading inside setUp function
# We need to test on relatively large models (aka >1b parameters otherwise the quantiztion may not work as expected)
# Therefore here we use only bloom-1b3 to test our module
model_name = "bigscience/bloom-1b7"
# Constant values
EXPECTED_RELATIVE_DIFFERENCE = (
2.109659552692574 # This was obtained on a RTX Titan so the number might slightly change
)
input_text = "Hello my name is"
EXPECTED_OUTPUTS = set()
EXPECTED_OUTPUTS.add("Hello my name is John and I am a professional photographer. I")
EXPECTED_OUTPUTS.add("Hello my name is John.\nI am a friend of your father.\n")
MAX_NEW_TOKENS = 10
def setUp(self):
# Models and tokenizer
self.tokenizer = AutoTokenizer.from_pretrained(self.model_name)
class Bnb4BitTest(Base4bitTest):
def setUp(self):
super().setUp()
# Models and tokenizer
self.model_fp16 = AutoModelForCausalLM.from_pretrained(
self.model_name, torch_dtype=torch.float16, device_map="auto"
)
self.model_4bit = AutoModelForCausalLM.from_pretrained(self.model_name, load_in_4bit=True, device_map="auto")
def tearDown(self):
r"""
TearDown function needs to be called at the end of each test to free the GPU memory and cache, also to
avoid unexpected behaviors. Please see: https://discuss.pytorch.org/t/how-can-we-release-gpu-memory-cache/14530/27
"""
del self.model_fp16
del self.model_4bit
gc.collect()
torch.cuda.empty_cache()
def test_memory_footprint(self):
r"""
A simple test to check if the model conversion has been done correctly by checking on the
memory footprint of the converted model and the class type of the linear layers of the converted models
"""
from bitsandbytes.nn import Params4bit
mem_fp16 = self.model_fp16.get_memory_footprint()
mem_4bit = self.model_4bit.get_memory_footprint()
self.assertAlmostEqual(mem_fp16 / mem_4bit, self.EXPECTED_RELATIVE_DIFFERENCE)
self.assertTrue(self.model_4bit.transformer.h[0].mlp.dense_4h_to_h.weight.__class__ == Params4bit)
def test_linear_are_4bit(self):
r"""
A simple test to check if the model conversion has been done correctly by checking on the
memory footprint of the converted model and the class type of the linear layers of the converted models
"""
from transformers import T5PreTrainedModel
self.model_fp16.get_memory_footprint()
self.model_4bit.get_memory_footprint()
for name, module in self.model_4bit.named_modules():
if isinstance(module, torch.nn.Linear):
if name not in ["lm_head"] + T5PreTrainedModel._keep_in_fp32_modules:
# 4-bit parameters are packed in uint8 variables
self.assertTrue(module.weight.dtype == torch.uint8)
def test_generate_quality(self):
r"""
Test the generation quality of the quantized model and see that we are matching the expected output.
Given that we are operating on small numbers + the testing model is relatively small, we might not get
the same output across GPUs. So we'll generate few tokens (5-10) and check their output.
"""
encoded_input = self.tokenizer(self.input_text, return_tensors="pt")
output_sequences = self.model_4bit.generate(input_ids=encoded_input["input_ids"].to(0), max_new_tokens=10)
self.assertIn(self.tokenizer.decode(output_sequences[0], skip_special_tokens=True), self.EXPECTED_OUTPUTS)
def test_generate_quality_config(self):
r"""
Test that loading the model with the config is equivalent
"""
bnb_config = BitsAndBytesConfig()
bnb_config.load_in_4bit = True
model_4bit_from_config = AutoModelForCausalLM.from_pretrained(
self.model_name, quantization_config=bnb_config, device_map="auto"
)
encoded_input = self.tokenizer(self.input_text, return_tensors="pt")
output_sequences = model_4bit_from_config.generate(
input_ids=encoded_input["input_ids"].to(0), max_new_tokens=10
)
self.assertIn(self.tokenizer.decode(output_sequences[0], skip_special_tokens=True), self.EXPECTED_OUTPUTS)
def test_raise_on_save_pretrained(self):
r"""
Test whether trying to save a model after converting it in 8-bit will throw a warning.
"""
with self.assertRaises(NotImplementedError), tempfile.TemporaryDirectory() as tmpdirname:
self.model_4bit.save_pretrained(tmpdirname)
def test_raise_if_config_and_load_in_4bit(self):
r"""
Test that loading the model with the config and `load_in_4bit` raises an error
"""
bnb_config = BitsAndBytesConfig()
with self.assertRaises(ValueError):
_ = AutoModelForCausalLM.from_pretrained(
self.model_name,
quantization_config=bnb_config,
load_in_4bit=True,
device_map="auto",
bnb_4bit_quant_type="nf4",
)
def test_device_and_dtype_assignment(self):
r"""
Test whether trying to cast (or assigning a device to) a model after converting it in 8-bit will throw an error.
Checks also if other models are casted correctly.
"""
with self.assertRaises(ValueError):
# Tries with `str`
self.model_4bit.to("cpu")
with self.assertRaises(ValueError):
# Tries with a `dtype``
self.model_4bit.to(torch.float16)
with self.assertRaises(ValueError):
# Tries with a `device`
self.model_4bit.to(torch.device("cuda:0"))
with self.assertRaises(ValueError):
# Tries with a `device`
self.model_4bit.float()
with self.assertRaises(ValueError):
# Tries with a `device`
self.model_4bit.half()
# Test if we did not break anything
encoded_input = self.tokenizer(self.input_text, return_tensors="pt")
self.model_fp16 = self.model_fp16.to(torch.float32)
_ = self.model_fp16.generate(input_ids=encoded_input["input_ids"].to(0), max_new_tokens=10)
# Check this does not throw an error
_ = self.model_fp16.to("cpu")
# Check this does not throw an error
_ = self.model_fp16.half()
# Check this does not throw an error
_ = self.model_fp16.float()
def test_fp32_4bit_conversion(self):
r"""
Test whether it is possible to mix both `4bit` and `fp32` weights when using `keep_in_fp32_modules` correctly.
"""
model = AutoModelForSeq2SeqLM.from_pretrained("t5-small", load_in_4bit=True, device_map="auto")
self.assertTrue(model.decoder.block[0].layer[2].DenseReluDense.wo.weight.dtype == torch.float32)
@require_bitsandbytes
@require_accelerate
@require_torch
@require_torch_gpu
@slow
class Bnb4BitT5Test(unittest.TestCase):
@classmethod
def setUpClass(cls):
cls.model_name = "t5-small"
cls.dense_act_model_name = "google/flan-t5-small" # flan-t5 uses dense-act instead of dense-relu-dense
cls.tokenizer = AutoTokenizer.from_pretrained(cls.model_name)
cls.input_text = "Translate in German: Hello, my dog is cute"
def tearDown(self):
r"""
TearDown function needs to be called at the end of each test to free the GPU memory and cache, also to
avoid unexpected behaviors. Please see: https://discuss.pytorch.org/t/how-can-we-release-gpu-memory-cache/14530/27
"""
gc.collect()
torch.cuda.empty_cache()
def test_inference_without_keep_in_fp32(self):
r"""
Test whether it is possible to mix both `4bit` and `fp32` weights when using `keep_in_fp32_modules` correctly.
`flan-t5-small` uses `T5DenseGatedActDense` whereas `t5-small` uses `T5DenseReluDense`. We need to test
both cases.
"""
from transformers import T5ForConditionalGeneration
modules = T5ForConditionalGeneration._keep_in_fp32_modules
T5ForConditionalGeneration._keep_in_fp32_modules = None
# test with `t5-small`
model = T5ForConditionalGeneration.from_pretrained(self.model_name, load_in_4bit=True, device_map="auto")
encoded_input = self.tokenizer(self.input_text, return_tensors="pt").to(0)
_ = model.generate(**encoded_input)
# test with `flan-t5-small`
model = T5ForConditionalGeneration.from_pretrained(
self.dense_act_model_name, load_in_4bit=True, device_map="auto"
)
encoded_input = self.tokenizer(self.input_text, return_tensors="pt").to(0)
_ = model.generate(**encoded_input)
T5ForConditionalGeneration._keep_in_fp32_modules = modules
def test_inference_with_keep_in_fp32(self):
r"""
Test whether it is possible to mix both `4bit` and `fp32` weights when using `keep_in_fp32_modules` correctly.
`flan-t5-small` uses `T5DenseGatedActDense` whereas `t5-small` uses `T5DenseReluDense`. We need to test
both cases.
"""
import bitsandbytes as bnb
from transformers import T5ForConditionalGeneration
# test with `t5-small`
model = T5ForConditionalGeneration.from_pretrained(self.model_name, load_in_4bit=True, device_map="auto")
# there was a bug with decoders - this test checks that it is fixed
self.assertTrue(isinstance(model.decoder.block[0].layer[0].SelfAttention.q, bnb.nn.Linear4bit))
encoded_input = self.tokenizer(self.input_text, return_tensors="pt").to(0)
_ = model.generate(**encoded_input)
# test with `flan-t5-small`
model = T5ForConditionalGeneration.from_pretrained(
self.dense_act_model_name, load_in_4bit=True, device_map="auto"
)
encoded_input = self.tokenizer(self.input_text, return_tensors="pt").to(0)
_ = model.generate(**encoded_input)
class Classes4BitModelTest(Base4bitTest):
def setUp(self):
super().setUp()
# model_name
self.model_name = "bigscience/bloom-560m"
self.seq_to_seq_name = "t5-small"
# Different types of model
self.base_model = AutoModel.from_pretrained(self.model_name, load_in_4bit=True, device_map="auto")
# Sequence classification model
self.sequence_model = AutoModelForSequenceClassification.from_pretrained(
self.model_name, load_in_4bit=True, device_map="auto"
)
# CausalLM model
self.model_4bit = AutoModelForCausalLM.from_pretrained(self.model_name, load_in_4bit=True, device_map="auto")
# Seq2seq model
self.seq_to_seq_model = AutoModelForSeq2SeqLM.from_pretrained(
self.seq_to_seq_name, load_in_4bit=True, device_map="auto"
)
def tearDown(self):
r"""
TearDown function needs to be called at the end of each test to free the GPU memory and cache, also to
avoid unexpected behaviors. Please see: https://discuss.pytorch.org/t/how-can-we-release-gpu-memory-cache/14530/27
"""
del self.base_model
del self.sequence_model
del self.model_4bit
del self.seq_to_seq_model
gc.collect()
torch.cuda.empty_cache()
def test_correct_head_class(self):
r"""
A simple test to check if the last modules for some classes (AutoModelForCausalLM or SequenceClassification)
are kept in their native class.
"""
from bitsandbytes.nn import Params4bit
self.assertTrue(self.base_model.h[-1].mlp.dense_4h_to_h.weight.__class__ == Params4bit)
# Other heads should be nn.Parameter
self.assertTrue(self.model_4bit.lm_head.weight.__class__ == torch.nn.Parameter)
self.assertTrue(self.sequence_model.score.weight.__class__ == torch.nn.Parameter)
self.assertTrue(self.seq_to_seq_model.lm_head.weight.__class__ == torch.nn.Parameter)
class Pipeline4BitTest(Base4bitTest):
def setUp(self):
super().setUp()
def tearDown(self):
r"""
TearDown function needs to be called at the end of each test to free the GPU memory and cache, also to
avoid unexpected behaviors. Please see: https://discuss.pytorch.org/t/how-can-we-release-gpu-memory-cache/14530/27
"""
del self.pipe
gc.collect()
torch.cuda.empty_cache()
def test_pipeline(self):
r"""
The aim of this test is to verify that the mixed 4bit is compatible with `pipeline` from transformers. Since
we used pipline for inference speed benchmarking we want to make sure that this feature does not break anything
on pipline.
"""
# self._clear_cuda_cache()
self.pipe = pipeline(
"text-generation",
model=self.model_name,
model_kwargs={"device_map": "auto", "load_in_4bit": True, "torch_dtype": torch.float16},
max_new_tokens=self.MAX_NEW_TOKENS,
)
# Real second forward pass
pipeline_output = self.pipe(self.input_text)
self.assertIn(pipeline_output[0]["generated_text"], self.EXPECTED_OUTPUTS)
@require_torch_multi_gpu
class Bnb4bitTestMultiGpu(Base4bitTest):
def setUp(self):
super().setUp()
def test_multi_gpu_loading(self):
r"""
This tests that the model has been loaded and can be used correctly on a multi-GPU setup.
Let's just try to load a model on 2 GPUs and see if it works. The model we test has ~2GB of total, 3GB should suffice
"""
model_parallel = AutoModelForCausalLM.from_pretrained(
self.model_name, load_in_4bit=True, device_map="balanced"
)
# Check correct device map
self.assertEqual(set(model_parallel.hf_device_map.values()), {0, 1})
# Check that inference pass works on the model
encoded_input = self.tokenizer(self.input_text, return_tensors="pt")
# Second real batch
output_parallel = model_parallel.generate(input_ids=encoded_input["input_ids"].to(0), max_new_tokens=10)
self.assertIn(self.tokenizer.decode(output_parallel[0], skip_special_tokens=True), self.EXPECTED_OUTPUTS)
class Bnb4BitTestTraining(Base4bitTest):
def setUp(self):
self.model_name = "facebook/opt-350m"
super().setUp()
def test_training(self):
if version.parse(importlib_metadata.version("bitsandbytes")) < version.parse("0.37.0"):
return
# Step 1: freeze all parameters
model = AutoModelForCausalLM.from_pretrained(self.model_name, load_in_4bit=True, device_map="auto")
for param in model.parameters():
param.requires_grad = False # freeze the model - train adapters later
if param.ndim == 1:
# cast the small parameters (e.g. layernorm) to fp32 for stability
param.data = param.data.to(torch.float32)
# Step 2: add adapters
for _, module in model.named_modules():
if "OPTAttention" in repr(type(module)):
module.q_proj = LoRALayer(module.q_proj, rank=16)
module.k_proj = LoRALayer(module.k_proj, rank=16)
module.v_proj = LoRALayer(module.v_proj, rank=16)
# Step 3: dummy batch
batch = self.tokenizer("Test batch ", return_tensors="pt").to(0)
# Step 4: Check if the gradient is not None
with torch.cuda.amp.autocast():
out = model.forward(**batch)
out.logits.norm().backward()
for module in model.modules():
if isinstance(module, LoRALayer):
self.assertTrue(module.adapter[1].weight.grad is not None)
self.assertTrue(module.adapter[1].weight.grad.norm().item() > 0)
elif isinstance(module, nn.Embedding):
self.assertTrue(module.weight.grad is None)

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# coding=utf-8
# Copyright 2022 The HuggingFace Team Inc.
#
# 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 clone 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 gc
import tempfile
import unittest
from packaging import version
from transformers import (
AutoConfig,
AutoModel,
AutoModelForCausalLM,
AutoModelForSeq2SeqLM,
AutoModelForSequenceClassification,
AutoTokenizer,
BitsAndBytesConfig,
pipeline,
)
from transformers.testing_utils import (
is_accelerate_available,
is_torch_available,
require_accelerate,
require_bitsandbytes,
require_torch,
require_torch_gpu,
require_torch_multi_gpu,
slow,
)
from transformers.utils.versions import importlib_metadata
if is_accelerate_available():
from accelerate import PartialState
from accelerate.logging import get_logger
logger = get_logger(__name__)
_ = PartialState()
if is_torch_available():
import torch
import torch.nn as nn
class LoRALayer(nn.Module):
"""Wraps a linear layer with LoRA-like adapter - Used for testing purposes only"""
def __init__(self, module: nn.Module, rank: int):
super().__init__()
self.module = module
self.adapter = nn.Sequential(
nn.Linear(module.in_features, rank, bias=False),
nn.Linear(rank, module.out_features, bias=False),
)
small_std = (2.0 / (5 * min(module.in_features, module.out_features))) ** 0.5
nn.init.normal_(self.adapter[0].weight, std=small_std)
nn.init.zeros_(self.adapter[1].weight)
self.adapter.to(module.weight.device)
def forward(self, input, *args, **kwargs):
return self.module(input, *args, **kwargs) + self.adapter(input)
@require_bitsandbytes
@require_accelerate
@require_torch
@require_torch_gpu
@slow
class BaseMixedInt8Test(unittest.TestCase):
# We keep the constants inside the init function and model loading inside setUp function
# We need to test on relatively large models (aka >1b parameters otherwise the quantiztion may not work as expected)
# Therefore here we use only bloom-1b3 to test our module
model_name = "bigscience/bloom-1b7"
# Constant values
EXPECTED_RELATIVE_DIFFERENCE = (
1.540025 # This was obtained on a Quadro RTX 8000 so the number might slightly change
)
input_text = "Hello my name is"
EXPECTED_OUTPUT = "Hello my name is John.\nI am a friend of the family.\n"
MAX_NEW_TOKENS = 10
def setUp(self):
# Models and tokenizer
self.tokenizer = AutoTokenizer.from_pretrained(self.model_name)
class MixedInt8Test(BaseMixedInt8Test):
def setUp(self):
super().setUp()
# Models and tokenizer
self.model_fp16 = AutoModelForCausalLM.from_pretrained(
self.model_name, torch_dtype=torch.float16, device_map="auto"
)
self.model_8bit = AutoModelForCausalLM.from_pretrained(self.model_name, load_in_8bit=True, device_map="auto")
def tearDown(self):
r"""
TearDown function needs to be called at the end of each test to free the GPU memory and cache, also to
avoid unexpected behaviors. Please see: https://discuss.pytorch.org/t/how-can-we-release-gpu-memory-cache/14530/27
"""
del self.model_fp16
del self.model_8bit
gc.collect()
torch.cuda.empty_cache()
def test_memory_footprint(self):
r"""
A simple test to check if the model conversion has been done correctly by checking on the
memory footprint of the converted model and the class type of the linear layers of the converted models
"""
from bitsandbytes.nn import Int8Params
mem_fp16 = self.model_fp16.get_memory_footprint()
mem_8bit = self.model_8bit.get_memory_footprint()
self.assertAlmostEqual(mem_fp16 / mem_8bit, self.EXPECTED_RELATIVE_DIFFERENCE)
self.assertTrue(self.model_8bit.transformer.h[0].mlp.dense_4h_to_h.weight.__class__ == Int8Params)
def test_linear_are_8bit(self):
r"""
A simple test to check if the model conversion has been done correctly by checking on the
memory footprint of the converted model and the class type of the linear layers of the converted models
"""
from transformers import T5PreTrainedModel
self.model_fp16.get_memory_footprint()
self.model_8bit.get_memory_footprint()
for name, module in self.model_8bit.named_modules():
if isinstance(module, torch.nn.Linear):
if name not in ["lm_head"] + T5PreTrainedModel._keep_in_fp32_modules:
self.assertTrue(module.weight.dtype == torch.int8)
def test_generate_quality(self):
r"""
Test the generation quality of the quantized model and see that we are matching the expected output.
Given that we are operating on small numbers + the testing model is relatively small, we might not get
the same output across GPUs. So we'll generate few tokens (5-10) and check their output.
"""
encoded_input = self.tokenizer(self.input_text, return_tensors="pt")
output_sequences = self.model_8bit.generate(input_ids=encoded_input["input_ids"].to(0), max_new_tokens=10)
self.assertEqual(self.tokenizer.decode(output_sequences[0], skip_special_tokens=True), self.EXPECTED_OUTPUT)
def test_generate_quality_config(self):
r"""
Test that loading the model with the config is equivalent
"""
bnb_config = BitsAndBytesConfig()
bnb_config.load_in_8bit = True
model_8bit_from_config = AutoModelForCausalLM.from_pretrained(
self.model_name, quantization_config=bnb_config, device_map="auto"
)
encoded_input = self.tokenizer(self.input_text, return_tensors="pt")
output_sequences = model_8bit_from_config.generate(
input_ids=encoded_input["input_ids"].to(0), max_new_tokens=10
)
self.assertEqual(self.tokenizer.decode(output_sequences[0], skip_special_tokens=True), self.EXPECTED_OUTPUT)
def test_warns_save_pretrained(self):
r"""
Test whether trying to save a model after converting it in 8-bit will throw a warning.
"""
with self.assertWarns(UserWarning), tempfile.TemporaryDirectory() as tmpdirname:
self.model_8bit.save_pretrained(tmpdirname)
def test_raise_if_config_and_load_in_8bit(self):
r"""
Test that loading the model with the config and `load_in_8bit` raises an error
"""
bnb_config = BitsAndBytesConfig()
with self.assertRaises(ValueError):
_ = AutoModelForCausalLM.from_pretrained(
self.model_name,
quantization_config=bnb_config,
load_in_8bit=True,
device_map="auto",
llm_int8_enable_fp32_cpu_offload=True,
)
def test_device_and_dtype_assignment(self):
r"""
Test whether trying to cast (or assigning a device to) a model after converting it in 8-bit will throw an error.
Checks also if other models are casted correctly.
"""
with self.assertRaises(ValueError):
# Tries with `str`
self.model_8bit.to("cpu")
with self.assertRaises(ValueError):
# Tries with a `dtype``
self.model_8bit.to(torch.float16)
with self.assertRaises(ValueError):
# Tries with a `device`
self.model_8bit.to(torch.device("cuda:0"))
with self.assertRaises(ValueError):
# Tries with a `device`
self.model_8bit.float()
with self.assertRaises(ValueError):
# Tries with a `device`
self.model_8bit.half()
# Test if we did not break anything
encoded_input = self.tokenizer(self.input_text, return_tensors="pt")
self.model_fp16 = self.model_fp16.to(torch.float32)
_ = self.model_fp16.generate(input_ids=encoded_input["input_ids"].to(0), max_new_tokens=10)
# Check this does not throw an error
_ = self.model_fp16.to("cpu")
# Check this does not throw an error
_ = self.model_fp16.half()
# Check this does not throw an error
_ = self.model_fp16.float()
def test_fp32_int8_conversion(self):
r"""
Test whether it is possible to mix both `int8` and `fp32` weights when using `keep_in_fp32_modules` correctly.
"""
model = AutoModelForSeq2SeqLM.from_pretrained("t5-small", load_in_8bit=True, device_map="auto")
self.assertTrue(model.decoder.block[0].layer[2].DenseReluDense.wo.weight.dtype == torch.float32)
def test_int8_serialization(self):
r"""
Test whether it is possible to serialize a model in 8-bit.
"""
from bitsandbytes.nn import Int8Params
with tempfile.TemporaryDirectory() as tmpdirname:
self.model_8bit.save_pretrained(tmpdirname)
# check that the file `quantization_config` is present
config = AutoConfig.from_pretrained(tmpdirname)
self.assertTrue(hasattr(config, "quantization_config"))
model_from_saved = AutoModelForCausalLM.from_pretrained(tmpdirname, load_in_8bit=True, device_map="auto")
self.assertTrue(model_from_saved.transformer.h[0].mlp.dense_4h_to_h.weight.__class__ == Int8Params)
self.assertTrue(hasattr(model_from_saved.transformer.h[0].mlp.dense_4h_to_h.weight, "SCB"))
# generate
encoded_input = self.tokenizer(self.input_text, return_tensors="pt")
output_sequences = model_from_saved.generate(input_ids=encoded_input["input_ids"].to(0), max_new_tokens=10)
self.assertEqual(
self.tokenizer.decode(output_sequences[0], skip_special_tokens=True), self.EXPECTED_OUTPUT
)
def test_int8_serialization_sharded(self):
r"""
Test whether it is possible to serialize a model in 8-bit - sharded version.
"""
from bitsandbytes.nn import Int8Params
with tempfile.TemporaryDirectory() as tmpdirname:
self.model_8bit.save_pretrained(tmpdirname, max_shard_size="200MB")
# check that the file `quantization_config` is present
config = AutoConfig.from_pretrained(tmpdirname)
self.assertTrue(hasattr(config, "quantization_config"))
model_from_saved = AutoModelForCausalLM.from_pretrained(tmpdirname)
self.assertTrue(model_from_saved.transformer.h[0].mlp.dense_4h_to_h.weight.__class__ == Int8Params)
self.assertTrue(hasattr(model_from_saved.transformer.h[0].mlp.dense_4h_to_h.weight, "SCB"))
# generate
encoded_input = self.tokenizer(self.input_text, return_tensors="pt")
output_sequences = model_from_saved.generate(input_ids=encoded_input["input_ids"].to(0), max_new_tokens=10)
self.assertEqual(
self.tokenizer.decode(output_sequences[0], skip_special_tokens=True), self.EXPECTED_OUTPUT
)
def test_int8_from_pretrained(self):
r"""
Test whether loading a 8bit model from the Hub works as expected
"""
from bitsandbytes.nn import Int8Params
model_id = "ybelkada/bloom-1b7-8bit"
model = AutoModelForCausalLM.from_pretrained(model_id)
self.assertTrue(model.transformer.h[0].mlp.dense_4h_to_h.weight.__class__ == Int8Params)
self.assertTrue(hasattr(model.transformer.h[0].mlp.dense_4h_to_h.weight, "SCB"))
# generate
encoded_input = self.tokenizer(self.input_text, return_tensors="pt")
output_sequences = model.generate(input_ids=encoded_input["input_ids"].to(0), max_new_tokens=10)
self.assertEqual(self.tokenizer.decode(output_sequences[0], skip_special_tokens=True), self.EXPECTED_OUTPUT)
@require_bitsandbytes
@require_accelerate
@require_torch
@require_torch_gpu
@slow
class MixedInt8T5Test(unittest.TestCase):
@classmethod
def setUpClass(cls):
cls.model_name = "t5-small"
cls.dense_act_model_name = "google/flan-t5-small" # flan-t5 uses dense-act instead of dense-relu-dense
cls.tokenizer = AutoTokenizer.from_pretrained(cls.model_name)
cls.input_text = "Translate in German: Hello, my dog is cute"
def tearDown(self):
r"""
TearDown function needs to be called at the end of each test to free the GPU memory and cache, also to
avoid unexpected behaviors. Please see: https://discuss.pytorch.org/t/how-can-we-release-gpu-memory-cache/14530/27
"""
gc.collect()
torch.cuda.empty_cache()
def test_inference_without_keep_in_fp32(self):
r"""
Test whether it is possible to mix both `int8` and `fp32` weights when using `keep_in_fp32_modules` correctly.
`flan-t5-small` uses `T5DenseGatedActDense` whereas `t5-small` uses `T5DenseReluDense`. We need to test
both cases.
"""
from transformers import T5ForConditionalGeneration
modules = T5ForConditionalGeneration._keep_in_fp32_modules
T5ForConditionalGeneration._keep_in_fp32_modules = None
# test with `t5-small`
model = T5ForConditionalGeneration.from_pretrained(self.model_name, load_in_8bit=True, device_map="auto")
encoded_input = self.tokenizer(self.input_text, return_tensors="pt").to(0)
_ = model.generate(**encoded_input)
# test with `flan-t5-small`
model = T5ForConditionalGeneration.from_pretrained(
self.dense_act_model_name, load_in_8bit=True, device_map="auto"
)
encoded_input = self.tokenizer(self.input_text, return_tensors="pt").to(0)
_ = model.generate(**encoded_input)
T5ForConditionalGeneration._keep_in_fp32_modules = modules
def test_inference_with_keep_in_fp32(self):
r"""
Test whether it is possible to mix both `int8` and `fp32` weights when using `keep_in_fp32_modules` correctly.
`flan-t5-small` uses `T5DenseGatedActDense` whereas `t5-small` uses `T5DenseReluDense`. We need to test
both cases.
"""
import bitsandbytes as bnb
from transformers import T5ForConditionalGeneration
# test with `t5-small`
model = T5ForConditionalGeneration.from_pretrained(self.model_name, load_in_8bit=True, device_map="auto")
# there was a bug with decoders - this test checks that it is fixed
self.assertTrue(isinstance(model.decoder.block[0].layer[0].SelfAttention.q, bnb.nn.Linear8bitLt))
encoded_input = self.tokenizer(self.input_text, return_tensors="pt").to(0)
_ = model.generate(**encoded_input)
# test with `flan-t5-small`
model = T5ForConditionalGeneration.from_pretrained(
self.dense_act_model_name, load_in_8bit=True, device_map="auto"
)
encoded_input = self.tokenizer(self.input_text, return_tensors="pt").to(0)
_ = model.generate(**encoded_input)
def test_inference_with_keep_in_fp32_serialized(self):
r"""
Test whether it is possible to mix both `int8` and `fp32` weights when using `keep_in_fp32_modules` correctly on
a serialized model.
`flan-t5-small` uses `T5DenseGatedActDense` whereas `t5-small` uses `T5DenseReluDense`. We need to test
both cases.
"""
import bitsandbytes as bnb
from transformers import T5ForConditionalGeneration
# test with `t5-small`
model = T5ForConditionalGeneration.from_pretrained(self.model_name, load_in_8bit=True, device_map="auto")
with tempfile.TemporaryDirectory() as tmp_dir:
model.save_pretrained(tmp_dir)
model = T5ForConditionalGeneration.from_pretrained(tmp_dir)
# there was a bug with decoders - this test checks that it is fixed
self.assertTrue(isinstance(model.decoder.block[0].layer[0].SelfAttention.q, bnb.nn.Linear8bitLt))
encoded_input = self.tokenizer(self.input_text, return_tensors="pt").to(0)
_ = model.generate(**encoded_input)
# test with `flan-t5-small`
model = T5ForConditionalGeneration.from_pretrained(
self.dense_act_model_name, load_in_8bit=True, device_map="auto"
)
encoded_input = self.tokenizer(self.input_text, return_tensors="pt").to(0)
_ = model.generate(**encoded_input)
class MixedInt8ModelClassesTest(BaseMixedInt8Test):
def setUp(self):
super().setUp()
# model_name
self.model_name = "bigscience/bloom-560m"
self.seq_to_seq_name = "t5-small"
# Different types of model
self.base_model = AutoModel.from_pretrained(self.model_name, load_in_8bit=True, device_map="auto")
# Sequence classification model
self.sequence_model = AutoModelForSequenceClassification.from_pretrained(
self.model_name, load_in_8bit=True, device_map="auto"
)
# CausalLM model
self.model_8bit = AutoModelForCausalLM.from_pretrained(self.model_name, load_in_8bit=True, device_map="auto")
# Seq2seq model
self.seq_to_seq_model = AutoModelForSeq2SeqLM.from_pretrained(
self.seq_to_seq_name, load_in_8bit=True, device_map="auto"
)
def tearDown(self):
r"""
TearDown function needs to be called at the end of each test to free the GPU memory and cache, also to
avoid unexpected behaviors. Please see: https://discuss.pytorch.org/t/how-can-we-release-gpu-memory-cache/14530/27
"""
del self.base_model
del self.sequence_model
del self.model_8bit
del self.seq_to_seq_model
gc.collect()
torch.cuda.empty_cache()
def test_correct_head_class(self):
r"""
A simple test to check if the last modules for some classes (AutoModelForCausalLM or SequenceClassification)
are kept in their native class.
"""
from bitsandbytes.nn import Int8Params
# last param of a base model should be a linear8bit module
self.assertTrue(self.base_model.h[-1].mlp.dense_4h_to_h.weight.__class__ == Int8Params)
# Other heads should be nn.Parameter
self.assertTrue(self.model_8bit.lm_head.weight.__class__ == torch.nn.Parameter)
self.assertTrue(self.sequence_model.score.weight.__class__ == torch.nn.Parameter)
self.assertTrue(self.seq_to_seq_model.lm_head.weight.__class__ == torch.nn.Parameter)
class MixedInt8TestPipeline(BaseMixedInt8Test):
def setUp(self):
super().setUp()
def tearDown(self):
r"""
TearDown function needs to be called at the end of each test to free the GPU memory and cache, also to
avoid unexpected behaviors. Please see: https://discuss.pytorch.org/t/how-can-we-release-gpu-memory-cache/14530/27
"""
del self.pipe
gc.collect()
torch.cuda.empty_cache()
def test_pipeline(self):
r"""
The aim of this test is to verify that the mixed int8 is compatible with `pipeline` from transformers. Since
we used pipline for inference speed benchmarking we want to make sure that this feature does not break anything
on pipline.
"""
# self._clear_cuda_cache()
self.pipe = pipeline(
"text-generation",
model=self.model_name,
model_kwargs={"device_map": "auto", "load_in_8bit": True},
max_new_tokens=self.MAX_NEW_TOKENS,
)
# Real second forward pass
pipeline_output = self.pipe(self.input_text)
self.assertEqual(pipeline_output[0]["generated_text"], self.EXPECTED_OUTPUT)
@require_torch_multi_gpu
class MixedInt8TestMultiGpu(BaseMixedInt8Test):
def setUp(self):
super().setUp()
def test_multi_gpu_loading(self):
r"""
This tests that the model has been loaded and can be used correctly on a multi-GPU setup.
Let's just try to load a model on 2 GPUs and see if it works. The model we test has ~2GB of total, 3GB should suffice
"""
model_parallel = AutoModelForCausalLM.from_pretrained(
self.model_name, load_in_8bit=True, device_map="balanced"
)
# Check correct device map
self.assertEqual(set(model_parallel.hf_device_map.values()), {0, 1})
# Check that inference pass works on the model
encoded_input = self.tokenizer(self.input_text, return_tensors="pt")
# Second real batch
output_parallel = model_parallel.generate(input_ids=encoded_input["input_ids"].to(0), max_new_tokens=10)
self.assertEqual(self.tokenizer.decode(output_parallel[0], skip_special_tokens=True), self.EXPECTED_OUTPUT)
@require_torch_multi_gpu
class MixedInt8TestCpuGpu(BaseMixedInt8Test):
def setUp(self):
super().setUp()
def check_inference_correctness(self, model):
# Check that inference pass works on the model
encoded_input = self.tokenizer(self.input_text, return_tensors="pt")
# Check the exactness of the results
output_parallel = model.generate(input_ids=encoded_input["input_ids"].to(0), max_new_tokens=10)
# Get the generation
output_text = self.tokenizer.decode(output_parallel[0], skip_special_tokens=True)
self.assertEqual(output_text, self.EXPECTED_OUTPUT)
def test_cpu_gpu_loading_random_device_map(self):
r"""
A test to check is dispatching a model on cpu & gpu works correctly using a random `device_map`.
"""
device_map = {
"transformer.word_embeddings": 0,
"transformer.word_embeddings_layernorm": 0,
"lm_head": 0,
"transformer.h.0": "cpu",
"transformer.h.1": "cpu",
"transformer.h.2": 0,
"transformer.h.3": 0,
"transformer.h.4": 0,
"transformer.h.5": 0,
"transformer.h.6": 0,
"transformer.h.7": 0,
"transformer.h.8": 0,
"transformer.h.9": 1,
"transformer.h.10": 0,
"transformer.h.11": 1,
"transformer.h.12": 0,
"transformer.h.13": 0,
"transformer.h.14": 1,
"transformer.h.15": 0,
"transformer.h.16": 0,
"transformer.h.17": 1,
"transformer.h.18": 1,
"transformer.h.19": 0,
"transformer.h.20": 1,
"transformer.h.21": 1,
"transformer.h.22": 0,
"transformer.h.23": 0,
"transformer.ln_f": 1,
}
bnb_config = BitsAndBytesConfig(llm_int8_enable_fp32_cpu_offload=True)
model_8bit = AutoModelForCausalLM.from_pretrained(
self.model_name,
device_map=device_map,
quantization_config=bnb_config,
)
# Check that the model has been correctly set on device 0, 1, and `cpu`.
self.assertEqual(set(model_8bit.hf_device_map.values()), {0, 1, "cpu"})
self.check_inference_correctness(model_8bit)
def test_cpu_gpu_loading_custom_device_map(self):
r"""
A test to check is dispatching a model on cpu & gpu works correctly using a custom `device_map`.
This time the device map is more organized than the test above and uses the abstraction
`transformer.h` to encapsulate all the decoder layers.
"""
device_map = {
"transformer.word_embeddings": "cpu",
"transformer.word_embeddings_layernorm": "cpu",
"lm_head": "cpu",
"transformer.h": 0,
"transformer.ln_f": 1,
}
bnb_config = BitsAndBytesConfig(llm_int8_enable_fp32_cpu_offload=True)
# Load model
model_8bit = AutoModelForCausalLM.from_pretrained(
self.model_name,
device_map=device_map,
quantization_config=bnb_config,
)
# Check that the model has been correctly set on device 0, 1, and `cpu`.
self.assertEqual(set(model_8bit.hf_device_map.values()), {0, 1, "cpu"})
self.check_inference_correctness(model_8bit)
def test_cpu_gpu_disk_loading_custom_device_map(self):
r"""
A test to check is dispatching a model on cpu & gpu works correctly using a custom `device_map`.
This time we also add `disk` on the device_map.
"""
device_map = {
"transformer.word_embeddings": 0,
"transformer.word_embeddings_layernorm": "cpu",
"lm_head": 0,
"transformer.h": 1,
"transformer.ln_f": "disk",
}
bnb_config = BitsAndBytesConfig(llm_int8_enable_fp32_cpu_offload=True)
with tempfile.TemporaryDirectory() as tmpdirname:
# Load model
model_8bit = AutoModelForCausalLM.from_pretrained(
self.model_name,
device_map=device_map,
quantization_config=bnb_config,
offload_folder=tmpdirname,
)
# Check that the model has been correctly set on device 0, 1, and `cpu`.
self.assertEqual(set(model_8bit.hf_device_map.values()), {0, 1, "cpu", "disk"})
self.check_inference_correctness(model_8bit)
def test_cpu_gpu_disk_loading_custom_device_map_kwargs(self):
r"""
A test to check is dispatching a model on cpu & gpu works correctly using a custom `device_map`.
This time we also add `disk` on the device_map - using the kwargs directly instead of the quantization config
"""
device_map = {
"transformer.word_embeddings": 0,
"transformer.word_embeddings_layernorm": "cpu",
"lm_head": 0,
"transformer.h": 1,
"transformer.ln_f": "disk",
}
with tempfile.TemporaryDirectory() as tmpdirname:
# Load model
model_8bit = AutoModelForCausalLM.from_pretrained(
self.model_name,
device_map=device_map,
llm_int8_enable_fp32_cpu_offload=True,
offload_folder=tmpdirname,
)
# Check that the model has been correctly set on device 0, 1, and `cpu`.
self.assertEqual(set(model_8bit.hf_device_map.values()), {0, 1, "cpu", "disk"})
self.check_inference_correctness(model_8bit)
class MixedInt8TestTraining(BaseMixedInt8Test):
def setUp(self):
self.model_name = "facebook/opt-350m"
super().setUp()
def test_training(self):
if version.parse(importlib_metadata.version("bitsandbytes")) < version.parse("0.37.0"):
return
# Step 1: freeze all parameters
model = AutoModelForCausalLM.from_pretrained(self.model_name, load_in_8bit=True, device_map="auto")
for param in model.parameters():
param.requires_grad = False # freeze the model - train adapters later
if param.ndim == 1:
# cast the small parameters (e.g. layernorm) to fp32 for stability
param.data = param.data.to(torch.float32)
# Step 2: add adapters
for _, module in model.named_modules():
if "OPTAttention" in repr(type(module)):
module.q_proj = LoRALayer(module.q_proj, rank=16)
module.k_proj = LoRALayer(module.k_proj, rank=16)
module.v_proj = LoRALayer(module.v_proj, rank=16)
# Step 3: dummy batch
batch = self.tokenizer("Test batch ", return_tensors="pt").to(0)
# Step 4: Check if the gradient is not None
with torch.cuda.amp.autocast():
out = model.forward(**batch)
out.logits.norm().backward()
for module in model.modules():
if isinstance(module, LoRALayer):
self.assertTrue(module.adapter[1].weight.grad is not None)
self.assertTrue(module.adapter[1].weight.grad.norm().item() > 0)
elif isinstance(module, nn.Embedding):
self.assertTrue(module.weight.grad is None)