
* toctree * not-doctested.txt * collapse sections * feedback * update * rewrite get started sections * fixes * fix * loading models * fix * customize models * share * fix link * contribute part 1 * contribute pt 2 * fix toctree * tokenization pt 1 * Add new model (#32615) * v1 - working version * fix * fix * fix * fix * rename to correct name * fix title * fixup * rename files * fix * add copied from on tests * rename to `FalconMamba` everywhere and fix bugs * fix quantization + accelerate * fix copies * add `torch.compile` support * fix tests * fix tests and add slow tests * copies on config * merge the latest changes * fix tests * add few lines about instruct * Apply suggestions from code review Co-authored-by: Arthur <48595927+ArthurZucker@users.noreply.github.com> * fix * fix tests --------- Co-authored-by: Arthur <48595927+ArthurZucker@users.noreply.github.com> * "to be not" -> "not to be" (#32636) * "to be not" -> "not to be" * Update sam.md * Update trainer.py * Update modeling_utils.py * Update test_modeling_utils.py * Update test_modeling_utils.py * fix hfoption tag * tokenization pt. 2 * image processor * fix toctree * backbones * feature extractor * fix file name * processor * update not-doctested * update * make style * fix toctree * revision * make fixup * fix toctree * fix * make style * fix hfoption tag * pipeline * pipeline gradio * pipeline web server * add pipeline * fix toctree * not-doctested * prompting * llm optims * fix toctree * fixes * cache * text generation * fix * chat pipeline * chat stuff * xla * torch.compile * cpu inference * toctree * gpu inference * agents and tools * gguf/tiktoken * finetune * toctree * trainer * trainer pt 2 * optims * optimizers * accelerate * parallelism * fsdp * update * distributed cpu * hardware training * gpu training * gpu training 2 * peft * distrib debug * deepspeed 1 * deepspeed 2 * chat toctree * quant pt 1 * quant pt 2 * fix toctree * fix * fix * quant pt 3 * quant pt 4 * serialization * torchscript * scripts * tpu * review * model addition timeline * modular * more reviews * reviews * fix toctree * reviews reviews * continue reviews * more reviews * modular transformers * more review * zamba2 * fix * all frameworks * pytorch * supported model frameworks * flashattention * rm check_table * not-doctested.txt * rm check_support_list.py * feedback * updates/feedback * review * feedback * fix * update * feedback * updates * update --------- Co-authored-by: Younes Belkada <49240599+younesbelkada@users.noreply.github.com> Co-authored-by: Arthur <48595927+ArthurZucker@users.noreply.github.com> Co-authored-by: Quentin Gallouédec <45557362+qgallouedec@users.noreply.github.com>
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VPTQ
Vector Post-Training Quantization (VPTQ) is a Post-Training Quantization (PTQ) method that leverages vector quantization to quantize LLMs at an extremely low bit-width (<2-bit). VPTQ can compress a 70B, even a 405B model, to 1-2 bits without retraining and still maintain a high-degree of accuracy. It is a lightweight quantization algorithm that takes ~17 hours to quantize a 405B model. VPTQ features agile quantization inference with low decoding overhead and high throughput and Time To First Token (TTFT).
Run the command below to install VPTQ which provides efficient kernels for inference on NVIDIA and AMD GPUs.
pip install vptq
The VPTQ-community provides a collection of VPTQ-quantized models. The model name contains information about its bitwidth (excluding cookbook, parameter, and padding overhead). Consider the [Meta-Llama-3.1-70B-Instruct-v8-k65536-256-woft] model as an example.
- The model name is Meta-Llama-3.1-70B-Instruct.
- The number of centroids is given by 65536 (2^16).
- The number of residual centroids is given by 256 (2^8).
The equivalent bit-width calculation is given by the following.
- index: log2(65536) = 16 / 8 = 2-bits
- residual index: log2(256) = 8 / 8 = 1-bit
- total bit-width: 2 + 1 = 3-bits
From here, estimate the model size by multiplying 70B * 3-bits / 8-bits/byte for a total of 26.25GB.
Load a VPTQ quantized model with [~PreTrainedModel.from_pretrained
].
from transformers import AutoTokenizer, AutoModelForCausalLM
quantized_model = AutoModelForCausalLM.from_pretrained(
"VPTQ-community/Meta-Llama-3.1-70B-Instruct-v16-k65536-65536-woft",
torch_dtype="auto",
device_map="auto"
)
To quantize your own model, refer to the VPTQ Quantization Algorithm Tutorial tutorial.
Benchmarks
VPTQ achieves better accuracy and higher throughput with lower quantization overhead across models of different sizes. The following experimental results are for reference only; VPTQ can achieve better outcomes under reasonable parameters, especially in terms of model accuracy and inference speed.
Model | bitwidth | W2↓ | C4↓ | AvgQA↑ | tok/s↑ | mem(GB) | cost/h↓ |
---|---|---|---|---|---|---|---|
LLaMA-2 7B | 2.02 | 6.13 | 8.07 | 58.2 | 39.9 | 2.28 | 2 |
2.26 | 5.95 | 7.87 | 59.4 | 35.7 | 2.48 | 3.1 | |
LLaMA-2 13B | 2.02 | 5.32 | 7.15 | 62.4 | 26.9 | 4.03 | 3.2 |
2.18 | 5.28 | 7.04 | 63.1 | 18.5 | 4.31 | 3.6 | |
LLaMA-2 70B | 2.07 | 3.93 | 5.72 | 68.6 | 9.7 | 19.54 | 19 |
2.11 | 3.92 | 5.71 | 68.7 | 9.7 | 20.01 | 19 |
Resources
See an example demo of VPTQ on the VPTQ Online Demo Space or try running the VPTQ inference notebook.
For more information, read the VPTQ paper.