[Training] Whether to support weight per_channel QAT

[hbwx24]

Describe the issue

The model weight is quantified per channel：

• weight_scale.shape=[64,],
• zero_point.shape=[64]. When using onnxruntime-train to do QAT, the following error is reported. Does onnxruntime-train support per_channel QAT?

  
  onnxruntime                1.16.3
  onnxruntime-extensions     0.9.0
  onnxruntime-gpu            1.16.3
  onnxruntime-training       1.16.3

onnxruntime/orttraining/orttraining/training_api/module.cc:538 onnxruntime::common::Status onnxruntime::training::api::Module::TrainStep(const std::vector&, std::vector&) [ONNXRuntimeError] : 6 : RUNTIME_EXCEPTION : Non-zero status code returned while running FakeQuant node. Name:'FakeQuant_token_260' Status Message: /home/xin.wei/workdir/quant/onnx2torch/onnxruntime-source/orttraining/orttraining/training_ops/cpu/quantization/fake_quant.cc:68 onnxruntime::common::Status onnxruntime::contrib::FakeQuant::Compute(onnxruntime::OpKernelContext*) const [with T = float] IsScalarOr1ElementVector(scale) was false. Quantization scale must be a scalar or 1D tensor of size 1.

### To reproduce

The model weight is quantified per channel：
 - weight_scale.shape=[64,], 
 - zero_point.shape=[64]. 
When using onnxruntime-train to do QAT, the following error is reported. Does onnxruntime-train support per_channel QAT?

onnxruntime 1.16.3 onnxruntime-extensions 0.9.0 onnxruntime-gpu 1.16.3 onnxruntime-training 1.16.3

orttraining/orttraining/training_api/module.cc:538 onnxruntime::common::Status onnxruntime::training::api::Module::TrainStep(const std::vector&, std::vector&) [ONNXRuntimeError] : 6 : RUNTIME_EXCEPTION : Non-zero status code returned while running FakeQuant node. Name:'FakeQuant_token_260' Status Message: /home/xin.wei/workdir/quant/onnx2torch/onnxruntime-source/orttraining/orttraining/training_ops/cpu/quantization/fake_quant.cc:68 onnxruntime::common::Status onnxruntime::contrib::FakeQuant::Compute(onnxruntime::OpKernelContext*) const [with T = float] IsScalarOr1ElementVector(scale) was false. Quantization scale must be a scalar or 1D tensor of size 1.

### Urgency

_No response_

### ONNX Runtime Installation

Built from Source

### ONNX Runtime Version or Commit ID

 1.16.3

### PyTorch Version

1.10

### Execution Provider

Default CPU, CUDA

### Execution Provider Library Version

_No response_

[baijumeswani]

@hbwx24 Thanks for trying out QAT. QAT with ONNX Runtime is in experimental stage at this time.

Looking through my own TODOs in the repository, it seems like per channel QAT is not supported yet.

I don't know if I can commit to having this feature completed soon, but I will try to address this feature before the next ONNX Runtime release (1.18).

[hbwx24]

@hbwx24 Thanks for trying out QAT. QAT with ONNX Runtime is in experimental stage at this time.

Looking through my own TODOs in the repository, it seems like per channel QAT is not supported yet.

I don't know if I can commit to having this feature completed soon, but I will try to address this feature before the next ONNX Runtime release (1.18).

Thank you very much

[yzg216]

I have also encountered this problem, and I am anxious to use it. If I develop it myself, can you tell me how to fix it? @baijumeswani

[github-actions[bot]]

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