Unified HuggingFace Checkpoint

We support exporting modelopt-optimized Huggingface models and Megatron Core models to a unified checkpoint format that can be deployed in various inference frameworks such as TensorRT-LLM, vLLM, and SGLang.

The workflow is as follows:

  1. Load the Huggingface models or Megatron Core models, quantize with modelopt , and export to the unified checkpoint format, where the layer structures and tensor names are aligned with the original checkpoint.

  2. Load the unified checkpoint in the supported inference framework for accelerated inference.

Export Quantized Model

The modelopt quantized model can be exported to the unified checkpoint format stored as

  1. A group of safetensors files, containing quantized model weights and scaling factors.

  2. A hf_quant_config.json file containing quantization configurations.

  3. Other json files that store the model structure information, tokenizer information, and metadata.

The export API (export_hf_checkpoint) can be used as follows:

from modelopt.torch.export import export_hf_checkpoint

with torch.inference_mode():
    export_hf_checkpoint(
        model,  # The quantized model.
        export_dir,  # The directory where the exported files will be stored.
    )

Deployment Support Matrix

Supported Quantization Formats

The unified HF export API supports the following quantization formats:

  1. FP8 - 8-bit floating point

  2. FP8_PB - 8-bit floating point with per-block scaling

  3. NVFP4 - NVIDIA 4-bit floating point

  4. NVFP4_AWQ - NVIDIA 4-bit floating point with AWQ optimization

  5. INT4_AWQ - 4-bit integer with AWQ optimization

  6. W4A8_AWQ - 4-bit weights and 8-bit activations with AWQ optimization

Framework-Specific Support

TensorRT-LLM

Models:

  • Llama 4, 3.1, 3.3 (FP8, NVFP4)

  • Qwen 3 (FP8, NVFP4)

  • Deepseek R1 (NVFP4)

  • Mixtral 8x7B (FP8, NVFP4)

  • Medusa (FP8)

  • Eagle (FP8)

Requirements: TensorRT-LLM v0.17.0 or later

vLLM

Models:

  • Llama 3.1, 3.3 (FP8, NVFP4)

  • Mixtral 8x7B (FP8)

  • Deepseek R1 (NVFP4)

Requirements: vLLM v0.9.1 or later

SGLang

Models:

  • Llama 3.1, 3.3 (FP8, NVFP4)

  • Deepseek R1 (NVFP4)

  • Llama 4 (FP8)

Requirements: SGLang v0.4.7 or later

Note: While other models and quantization formats may work, they have not been thoroughly tested and validated.

Deployment with Selected Inference Frameworks

Follow the TensorRT-LLM installation instructions.

Currently we support fp8 and nvfp4 quantized models for TensorRT-LLM deployment, you need v0.17.0 or later version of TensorRT-LLM.

To run modelopt quantized model from Huggingface model hub, e.g., nvidia/Llama-3.1-8B-Instruct-FP8, refer to the sample code below:

from tensorrt_llm import LLM, SamplingParams

def main():

    prompts = [
        "Hello, my name is",
        "The president of the United States is",
        "The capital of France is",
        "The future of AI is",
    ]
    sampling_params = SamplingParams(temperature=0.8, top_p=0.95)

    llm = LLM(model="nvidia/Llama-3.1-8B-Instruct-FP8")

    outputs = llm.generate(prompts, sampling_params)

    for output in outputs:
        prompt = output.prompt
        generated_text = output.outputs[0].text
        print(f"Prompt: {prompt!r}, Generated text: {generated_text!r}")

if __name__ == '__main__':
    main()

Follow vLLM installation instructions.

Currently we support fp8 quantized models (without fp8 kv cache) for vLLM deployment, you need v0.6.5 or later version of vLLM.

To run modelopt quantized model from Huggingface model hub, e.g., nvidia/Llama-3.1-8B-Instruct-FP8, refer to the sample code below:

from vllm import LLM, SamplingParams

def main():

    model_id = "nvidia/Llama-3.1-8B-Instruct-FP8"
    sampling_params = SamplingParams(temperature=0.8, top_p=0.9)

    prompts = [
        "Hello, my name is",
        "The president of the United States is",
        "The capital of France is",
        "The future of AI is",
    ]

    llm = LLM(model=model_id, quantization="modelopt")
    outputs = llm.generate(prompts, sampling_params)

    for output in outputs:
        prompt = output.prompt
        generated_text = output.outputs[0].text
        print(f"Prompt: {prompt!r}, Generated text: {generated_text!r}")

if __name__ == "__main__":
    main()

Follow the SGLang installation instructions.

Currently we support fp8 quantized models (without fp8 kv cache) for SGLang deployment, you need to use the main branch of SGLang (since Jan 6, 2025) and build it from source.

To run modelopt quantized model from Huggingface model hub, e.g., nvidia/Llama-3.1-8B-Instruct-FP8, refer to the sample code below:

import sglang as sgl

def main():

    prompts = [
        "Hello, my name is",
        "The president of the United States is",
        "The capital of France is",
        "The future of AI is",
    ]
    sampling_params = {"temperature": 0.8, "top_p": 0.95}
    llm = sgl.Engine(model_path="nvidia/Llama-3.1-8B-Instruct-FP8", quantization="modelopt")

    outputs = llm.generate(prompts, sampling_params)
    for prompt, output in zip(prompts, outputs):
        print("===============================")
        print(f"Prompt: {prompt}\nGenerated text: {output['text']}")

if __name__ == "__main__":
    main()