The [NVIDIA TensorRT Model Optimizer](https://github.com/NVIDIA/TensorRT-Model-Optimizer) is a library designed to optimize models for inference with NVIDIA GPUs. It includes tools for Post-Training Quantization (PTQ) and Quantization Aware Training (QAT) of Large Language Models (LLMs), Vision Language Models (VLMs), and diffusion models.
We recommend installing the library with:
```console
pip install nvidia-modelopt
```
## Quantizing HuggingFace Models with PTQ
You can quantize HuggingFace models using the example scripts provided in the TensorRT Model Optimizer repository. The primary script for LLM PTQ is typically found within the `examples/llm_ptq` directory.
Below is an example showing how to quantize a model using modelopt's PTQ API:
export_dir,# The directory where the exported files will be stored.
)
```
The quantized checkpoint can then be deployed with vLLM. As an example, the following code shows how to deploy `nvidia/Llama-3.1-8B-Instruct-FP8`, which is the FP8 quantized checkpoint derived from `meta-llama/Llama-3.1-8B-Instruct`, using vLLM:
```python
fromvllmimportLLM,SamplingParams
defmain():
model_id="nvidia/Llama-3.1-8B-Instruct-FP8"
# Ensure you specify quantization='modelopt' when loading the modelopt checkpoint