ModelOpt 0.27.0 Release

Deprecations

• Deprecate real quantization configs, please use mtq.compress <modelopt.torch.quantization.compress> API for model compression after quantization.

New Features

• New model support in the llm_ptq example: OpenAI Whisper.
• Blockwise FP8 quantization support in unified model export.
• Add quantization support to the Transformer Engine Linear module.
• Add support for SVDQuant. Currently, only simulation is available; real deployment (for example, TensorRT deployment) support is coming soon.
• To support distributed checkpoint resume expert-parallel (EP), modelopt_state in Megatron Core distributed checkpoint (used in NeMo and Megatron-LM) is stored differently. The legacy modelopt_state in the distributed checkpoint generated by previous modelopt version can still be loaded in 0.27 and 0.29 but will need to be stored in the new format.
• Add triton-based NVFP4 quantization kernel that delivers approximately 40% performance improvement over the previous implementation.
• Add a new API mtq.compress <modelopt.torch.quantization.compress> for model compression for weights after quantization.
• Add option to simplify ONNX model before quantization is performed.
• (Experimental) Improve support for ONNX models with custom TensorRT op:
  • Add support for --calibration_shapes flag.
  • Add automatic type and shape tensor propagation for full ORT support with TensorRT EP.

Known Issues

• Quantization of T5 models is broken. Please use nvidia-modelopt==0.25.0 with transformers<4.50 meanwhile.