✨ [diffusion][npu][quant] Add MXFP8 quantization support for Wan2.2 Diffusion on Ascend NPU (#20922)

Co-authored-by: ronnie_zheng <zl19940307@163.com>
Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>
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Junlin Wu
2026-05-07 21:30:56 +03:00
committed by GitHub
co-authored by ronnie_zheng github-actions[bot]
parent 7d397ad23d
commit 80a6014243
16 changed files with 706 additions and 144 deletions
@@ -5,16 +5,16 @@ To load already quantized models, simply load the model weights and config. Agai
SGLang support **mix-bits** quantization (independently defines and loads each layer depending on the type of quantification specified in the `quant_model_description'.json`). [Advanced mix-bits for MoE](https://github.com/sgl-project/sglang/pull/17361) in progress, will add independent quantization determination for the w13 (up-gate) and w2 (down) layers.
[ModelSlim on Ascend support](https://github.com/sgl-project/sglang/pull/14504)
| Quantization scheme | Layer type | A2 Supported | A3 Supported | A5 Supported | Diffusion models |
|-----------------------------------------------------------|--------------------------|:----------------------------------------:|:----------------------------------------:|:------------------------------------------:|:------------------------------------------:|
| W4A4 dynamic | Linear | **<span style="color: green;">√</span>** | **<span style="color: green;">√</span>** | **<span style="color: yellow;">TBD</span>** | **<span style="color: green;">√</span>** |
| W8A8 static | Linear | **<span style="color: green;">√</span>** | **<span style="color: green;">√</span>** | **<span style="color: yellow;">TBD</span>** | **<span style="color: green;">√</span>** |
| W8A8 dynamic | Linear | **<span style="color: green;">√</span>** | **<span style="color: green;">√</span>** | **<span style="color: yellow;">TBD</span>** | **<span style="color: green;">√</span>** |
| [MXFP8](https://github.com/sgl-project/sglang/pull/20922) | Linear | **<span style="color: red;">x</span>** | **<span style="color: red;">x</span>** | **<span style="color: blue;">WIP</span>** | **<span style="color: blue;">WIP</span>** |
| W4A4 dynamic | MoE | **<span style="color: green;">√</span>** | **<span style="color: green;">√</span>** | **<span style="color: yellow;">TBD</span>** | **<span style="color: red;">x</span>** |
| W4A8 dynamic | MoE | **<span style="color: green;">√</span>** | **<span style="color: green;">√</span>** | **<span style="color: yellow;">TBD</span>** | **<span style="color: red;">x</span>** |
| W8A8 dynamic | MoE | **<span style="color: green;">√</span>** | **<span style="color: green;">√</span>** | **<span style="color: yellow;">TBD</span>** | **<span style="color: red;">x</span>** |
| [MXFP8](https://github.com/sgl-project/sglang/pull/20922) | MoE | **<span style="color: red;">x</span>** | **<span style="color: red;">x</span>** | **<span style="color: blue;">WIP</span>** | **<span style="color: red;">x</span>** |
| Quantization scheme | `quant_type` in JSON | Scheme class | Layer type | A2 Supported | A3 Supported | A5 Supported | Diffusion models |
|-----------------------------------------------------------|----------------------|--------------------------|--------------------------|:----------------------------------------:|:----------------------------------------:|:------------------------------------------:|:------------------------------------------:|
| W4A4 dynamic | `W4A4_DYNAMIC` | `ModelSlimW4A4Int4` | Linear | **<span style="color: green;">√</span>** | **<span style="color: green;">√</span>** | **<span style="color: yellow;">TBD</span>** | **<span style="color: green;">√</span>** |
| W8A8 static | `W8A8` | `ModelSlimW8A8Int8` | Linear | **<span style="color: green;">√</span>** | **<span style="color: green;">√</span>** | **<span style="color: yellow;">TBD</span>** | **<span style="color: green;">√</span>** |
| W8A8 dynamic | `W8A8_DYNAMIC` | `ModelSlimW8A8Int8` | Linear | **<span style="color: green;">√</span>** | **<span style="color: green;">√</span>** | **<span style="color: yellow;">TBD</span>** | **<span style="color: green;">√</span>** |
| [MXFP8](https://github.com/sgl-project/sglang/pull/20922) | `W8A8_MXFP8` | `ModelSlimMXFP8Scheme` | Linear | **<span style="color: red;">x</span>** | **<span style="color: red;">x</span>** | **<span style="color: blue;">WIP</span>** | **<span style="color: green;">√</span>** (A5) |
| W4A4 dynamic | `W4A4_DYNAMIC` | `ModelSlimW4A4Int4` | MoE | **<span style="color: green;">√</span>** | **<span style="color: green;">√</span>** | **<span style="color: yellow;">TBD</span>** | **<span style="color: red;">x</span>** |
| W4A8 dynamic | `W4A8_DYNAMIC` | `ModelSlimW4A8Int8MoE` | MoE | **<span style="color: green;">√</span>** | **<span style="color: green;">√</span>** | **<span style="color: yellow;">TBD</span>** | **<span style="color: red;">x</span>** |
| W8A8 dynamic | `W8A8_DYNAMIC` | `ModelSlimW8A8Int8` | MoE | **<span style="color: green;">√</span>** | **<span style="color: green;">√</span>** | **<span style="color: yellow;">TBD</span>** | **<span style="color: red;">x</span>** |
| [MXFP8](https://github.com/sgl-project/sglang/pull/20922) | `W8A8_MXFP8` | `ModelSlimMXFP8Scheme` | MoE | **<span style="color: red;">x</span>** | **<span style="color: red;">x</span>** | **<span style="color: blue;">WIP</span>** | **<span style="color: red;">x</span>** |
[AWQ on Ascend support](https://github.com/sgl-project/sglang/pull/10158):
| Quantization scheme | Layer type | A2 Supported | A3 Supported | A5 Supported |
@@ -54,3 +54,81 @@ Compressed-tensors (LLM Compressor) on Ascend support:
| [GGUF (all types)](https://github.com/sgl-project/sglang/pull/17883) | MoE | **<span style="color: green;">√</span>** | **<span style="color: green;">√</span>** | **<span style="color: yellow;">TBD</span>** |
> Note: On Ascend, GGUF weights are pre-dequantized to FP16/BF16 during model loading to ensure optimal inference performance. This enables support for all GGUF quantization types (Q2_K, Q4_K_M, IQ4_XS, etc.) while maintaining high inference speed.
in progress
## Diffusion Model Quantization on Ascend NPU
SGLang-Diffusion supports MXFP8 online and offline quantization for diffusion models (such as Wan2.2) on Ascend NPUs. MXFP8 requires A5; the ModelSlim W8A8/W4A4 schemes work on A2/A3.
**Requirements for MXFP8:** CANN ≥ 8.0.RC3, Ascend A5
| Quantization method | `quant_type` in JSON | Scheme class | Mode | A2/A3 Supported | A5 Supported | Trigger |
|---------------------|-----------------------|-------------------------------|---------|:--------------------------------------------:|:----------------------------------------:|---------------------------------------------------|
| MXFP8 (W8A8) | — | `MXFP8Config` | Online | **<span style="color: red;">x</span>** | **<span style="color: green;">√</span>** | `--quantization mxfp8` |
| MXFP8 (W8A8) | `W8A8_MXFP8` | `ModelSlimMXFP8Scheme` | Offline | **<span style="color: red;">x</span>** | **<span style="color: green;">√</span>** | auto-detected from `quant_model_description.json` |
| W8A8 static | `W8A8` | `ModelSlimW8A8Int8` | Offline | **<span style="color: green;">√</span>** | **<span style="color: yellow;">TBD</span>** | auto-detected from `quant_model_description.json` |
| W8A8 dynamic | `W8A8_DYNAMIC` | `ModelSlimW8A8Int8` | Offline | **<span style="color: green;">√</span>** | **<span style="color: yellow;">TBD</span>** | auto-detected from `quant_model_description.json` |
| W4A4 dynamic | `W4A4_DYNAMIC` | `ModelSlimW4A4Int4` | Offline | **<span style="color: green;">√</span>** | **<span style="color: yellow;">TBD</span>** | auto-detected from `quant_model_description.json` |
### Online MXFP8 Quantization
Online quantization dynamically quantizes FP16/BF16 weights to MXFP8 at load time using `npu_dynamic_mx_quant` + `npu_quant_matmul` CANN kernels. Pass `--quantization mxfp8` to override auto-detection.
```bash
# Start the diffusion server with online MXFP8 quantization
sglang serve \
--model-path Wan-AI/Wan2.2-T2V-A14B-Diffusers \
--quantization mxfp8 \
--num-gpus 4
```
```bash
# One-shot generation
sglang generate \
--model-path Wan-AI/Wan2.2-T2V-A14B-Diffusers \
--quantization mxfp8 \
--prompt "a beautiful sunset over the mountains" \
--save-output
```
### Offline MXFP8 Quantization (ModelSlim)
For offline quantization, pre-quantize the model with msModelSlim and load the resulting checkpoint. The quantization scheme is auto-detected from `quant_model_description.json`, so no extra `--quantization` flag is needed.
**Step 1: Quantize with msModelSlim**
```bash
msmodelslim quant \
--model_path /path/to/wan2_2_float_weights \
--save_path /path/to/wan2_2_mxfp8_weights \
--device npu \
--model_type Wan2_2 \
--quant_type mxfp8 \
--trust_remote_code True
```
> Note: SGLang does not support quantized embeddings; disable embedding quantization when using msmodelslim.
**Step 2: Convert to Diffusers format**
msModelSlim saves quantized Wan2.2 weights in the original Wan format. Convert to Diffusers format using the provided repack script:
```bash
python python/sglang/multimodal_gen/tools/wan_repack.py \
--input-path /path/to/wan2_2_mxfp8_weights \
--output-path /path/to/wan2_2_mxfp8_diffusers
```
Then copy all files from the original Diffusers checkpoint (except the `transformer`/`transformer_2` folders) into the output directory.
**Step 3: Run inference**
```bash
sglang generate \
--model-path /path/to/wan2_2_mxfp8_diffusers \
--prompt "a beautiful sunset over the mountains" \
--save-output
```
For pre-quantized checkpoints available on ModelScope, see [modelscope/Eco-Tech](https://modelscope.cn/models/Eco-Tech).