Text Generation
Transformers
Safetensors
qwen3
feature-extraction
dflash
speculative-decoding
block-diffusion
draft-model
efficiency
qwen
diffusion-language-model
custom_code
text-generation-inference
Instructions to use PhysShell/Qwen3.6-35B-A3B-DFlash with libraries, inference providers, notebooks, and local apps. Follow these links to get started.
- Libraries
- Transformers
How to use PhysShell/Qwen3.6-35B-A3B-DFlash with Transformers:
# Use a pipeline as a high-level helper from transformers import pipeline pipe = pipeline("text-generation", model="PhysShell/Qwen3.6-35B-A3B-DFlash", trust_remote_code=True)# Load model directly from transformers import AutoTokenizer, AutoModel tokenizer = AutoTokenizer.from_pretrained("PhysShell/Qwen3.6-35B-A3B-DFlash", trust_remote_code=True) model = AutoModel.from_pretrained("PhysShell/Qwen3.6-35B-A3B-DFlash", trust_remote_code=True) - Notebooks
- Google Colab
- Kaggle
- Local Apps
- vLLM
How to use PhysShell/Qwen3.6-35B-A3B-DFlash with vLLM:
Install from pip and serve model
# Install vLLM from pip: pip install vllm # Start the vLLM server: vllm serve "PhysShell/Qwen3.6-35B-A3B-DFlash" # Call the server using curl (OpenAI-compatible API): curl -X POST "http://localhost:8000/v1/completions" \ -H "Content-Type: application/json" \ --data '{ "model": "PhysShell/Qwen3.6-35B-A3B-DFlash", "prompt": "Once upon a time,", "max_tokens": 512, "temperature": 0.5 }'Use Docker
docker model run hf.co/PhysShell/Qwen3.6-35B-A3B-DFlash
- SGLang
How to use PhysShell/Qwen3.6-35B-A3B-DFlash with SGLang:
Install from pip and serve model
# Install SGLang from pip: pip install sglang # Start the SGLang server: python3 -m sglang.launch_server \ --model-path "PhysShell/Qwen3.6-35B-A3B-DFlash" \ --host 0.0.0.0 \ --port 30000 # Call the server using curl (OpenAI-compatible API): curl -X POST "http://localhost:30000/v1/completions" \ -H "Content-Type: application/json" \ --data '{ "model": "PhysShell/Qwen3.6-35B-A3B-DFlash", "prompt": "Once upon a time,", "max_tokens": 512, "temperature": 0.5 }'Use Docker images
docker run --gpus all \ --shm-size 32g \ -p 30000:30000 \ -v ~/.cache/huggingface:/root/.cache/huggingface \ --env "HF_TOKEN=<secret>" \ --ipc=host \ lmsysorg/sglang:latest \ python3 -m sglang.launch_server \ --model-path "PhysShell/Qwen3.6-35B-A3B-DFlash" \ --host 0.0.0.0 \ --port 30000 # Call the server using curl (OpenAI-compatible API): curl -X POST "http://localhost:30000/v1/completions" \ -H "Content-Type: application/json" \ --data '{ "model": "PhysShell/Qwen3.6-35B-A3B-DFlash", "prompt": "Once upon a time,", "max_tokens": 512, "temperature": 0.5 }' - Docker Model Runner
How to use PhysShell/Qwen3.6-35B-A3B-DFlash with Docker Model Runner:
docker model run hf.co/PhysShell/Qwen3.6-35B-A3B-DFlash
| license: mit | |
| library_name: transformers | |
| pipeline_tag: text-generation | |
| tags: | |
| - dflash | |
| - speculative-decoding | |
| - block-diffusion | |
| - draft-model | |
| - efficiency | |
| - qwen | |
| - diffusion-language-model | |
| # Qwen3.6-35B-A3B-DFlash | |
| [**Paper**](https://arxiv.org/abs/2602.06036) | [**GitHub**](https://github.com/z-lab/dflash) | [**Blog**](https://z-lab.ai/projects/dflash/) | |
| **DFlash** is a speculative decoding method that uses a lightweight **block diffusion** model to draft multiple tokens in parallel. This is the drafter model, which must be paired with [Qwen/Qwen3.6-35B-A3B](https://huggingface.co/Qwen/Qwen3.6-35B-A3B). | |
| <div align="center"> | |
| <img src="assets/dflash_system.png" alt="DFlash Architecture" width="85%"> | |
| </div> | |
| ## Quick Start | |
| ### Installation | |
| vLLM: | |
| ```bash | |
| uv pip install vllm | |
| uv pip install -U vllm --torch-backend=auto --extra-index-url https://wheels.vllm.ai/nightly | |
| ``` | |
| SGLang: | |
| ```bash | |
| uv pip install "git+https://github.com/sgl-project/sglang.git@refs/pull/20547/head#subdirectory=python" | |
| ``` | |
| ### Launch Server | |
| vLLM: | |
| ```bash | |
| vllm serve Qwen/Qwen3.6-35B-A3B \ | |
| --speculative-config '{"method": "dflash", "model": "z-lab/Qwen3.6-35B-A3B-DFlash", "num_speculative_tokens": 15}' \ | |
| --attention-backend flash_attn \ | |
| --max-num-batched-tokens 32768 | |
| ``` | |
| SGLang: | |
| ```bash | |
| # Optional: enable schedule overlapping (experimental, may not be stable) | |
| # export SGLANG_ENABLE_SPEC_V2=1 | |
| # export SGLANG_ENABLE_DFLASH_SPEC_V2=1 | |
| # export SGLANG_ENABLE_OVERLAP_PLAN_STREAM=1 | |
| python -m sglang.launch_server \ | |
| --model-path Qwen/Qwen3.6-35B-A3B \ | |
| --speculative-algorithm DFLASH \ | |
| --speculative-draft-model-path z-lab/Qwen3.6-35B-A3B-DFlash \ | |
| --speculative-num-draft-tokens 16 \ | |
| --tp-size 1 \ | |
| --attention-backend fa3 \ | |
| --mem-fraction-static 0.75 \ | |
| --mamba-scheduler-strategy extra_buffer \ | |
| --trust-remote-code | |
| ``` | |
| > **Tip:** For long-context or agentic workloads, add `--speculative-dflash-draft-window-size WINDOW_SIZE` to enable sliding-window attention for the drafter. | |
| ### Usage | |
| ```python | |
| from openai import OpenAI | |
| client = OpenAI(base_url="http://localhost:30000/v1", api_key="EMPTY") | |
| response = client.chat.completions.create( | |
| model="Qwen/Qwen3.6-35B-A3B", | |
| messages=[{"role": "user", "content": "Write a quicksort in Python."}], | |
| max_tokens=4096, | |
| temperature=0.0 | |
| ) | |
| print(response.choices[0].message.content) | |
| ``` | |
| ## Benchmark Results | |
| **Setup:** Single NVIDIA B200, SGLang, thinking enabled, max output length 4096. We report end-to-end throughput, including prefill time. See our [GitHub repository](https://github.com/z-lab/dflash) for reproduction scripts. | |
| ### Throughput and Speedup | |
| DFlash achieves up to **2.9x** speedup at concurrency 1. | |
| _Tokens/sec (speedup vs. autoregressive baseline)_ | |
| **Block Size = 16** | |
| | Task | Concurrency | AR | **DFlash** | | |
| |---|---:|---:|---:| | |
| | Math500 | 1 | 234 | **682 (2.9x)** | | |
| | | 8 | 1266 | **3138 (2.5x)** | | |
| | | 16 | 1954 | **4813 (2.5x)** | | |
| | | 32 | 2755 | **6520 (2.4x)** | | |
| | GSM8K | 1 | 235 | **556 (2.4x)** | | |
| | | 8 | 1236 | **2564 (2.1x)** | | |
| | | 16 | 1886 | **3821 (2.0x)** | | |
| | | 32 | 2699 | **5239 (1.9x)** | | |
| | HumanEval | 1 | 238 | **603 (2.5x)** | | |
| | | 8 | 1255 | **2800 (2.2x)** | | |
| | | 16 | 1944 | **4208 (2.2x)** | | |
| | | 32 | 2767 | **5782 (2.1x)** | | |
| | MBPP | 1 | 235 | **559 (2.4x)** | | |
| | | 8 | 1224 | **2538 (2.1x)** | | |
| | | 16 | 1948 | **3816 (2.0x)** | | |
| | | 32 | 2780 | **5378 (1.9x)** | | |
| | MT-Bench | 1 | 233 | **442 (1.9x)** | | |
| | | 8 | 1238 | **2028 (1.6x)** | | |
| | | 16 | 1885 | **2997 (1.6x)** | | |
| | | 32 | 2633 | **4034 (1.5x)** | | |
| | Alpaca | 1 | 235 | **393 (1.7x)** | | |
| | | 8 | 1221 | **1782 (1.5x)** | | |
| | | 16 | 1844 | **2567 (1.4x)** | | |
| | | 32 | 2579 | **3689 (1.4x)** | | |
| **Block Size = 8** | |
| | Task | Concurrency | AR | **DFlash** | | |
| |---|---:|---:|---:| | |
| | Math500 | 1 | 234 | **617 (2.6x)** | | |
| | | 8 | 1266 | **2839 (2.2x)** | | |
| | | 16 | 1954 | **4465 (2.3x)** | | |
| | | 32 | 2755 | **6614 (2.4x)** | | |
| | GSM8K | 1 | 235 | **540 (2.3x)** | | |
| | | 8 | 1236 | **2466 (2.0x)** | | |
| | | 16 | 1886 | **3899 (2.1x)** | | |
| | | 32 | 2699 | **5713 (2.1x)** | | |
| | HumanEval | 1 | 238 | **561 (2.4x)** | | |
| | | 8 | 1255 | **2655 (2.1x)** | | |
| | | 16 | 1944 | **4135 (2.1x)** | | |
| | | 32 | 2767 | **6059 (2.2x)** | | |
| | MBPP | 1 | 235 | **497 (2.1x)** | | |
| | | 8 | 1224 | **2324 (1.9x)** | | |
| | | 16 | 1948 | **3636 (1.9x)** | | |
| | | 32 | 2780 | **4884 (1.8x)** | | |
| | MT-Bench | 1 | 233 | **438 (1.9x)** | | |
| | | 8 | 1238 | **2060 (1.7x)** | | |
| | | 16 | 1885 | **3182 (1.7x)** | | |
| | | 32 | 2633 | **4720 (1.8x)** | | |
| | Alpaca | 1 | 235 | **407 (1.7x)** | | |
| | | 8 | 1221 | **1880 (1.5x)** | | |
| | | 16 | 1844 | **2903 (1.6x)** | | |
| | | 32 | 2579 | **4115 (1.6x)** | | |
| ### Acceptance Length | |
| | Task | B8 | B16 | | |
| |---|---:|---:| | |
| | Math500 | 5.56 | 7.35 | | |
| | GSM8K | 5.21 | 6.73 | | |
| | HumanEval | 5.09 | 6.44 | | |
| | MBPP | 4.78 | 5.83 | | |
| | MT-Bench | 4.20 | 5.14 | | |
| | Alpaca | 3.94 | 4.62 | | |
| ## Acknowledgements | |
| Special thanks to [David Wang](https://davidwa.ng/) for his outstanding engineering support on this project. We are also grateful to [Modal](https://modal.com/), [InnoMatrix](https://innomatrix.ai), and [Yotta Labs](https://www.yottalabs.ai/) for providing the compute resources used to train this draft model. | |
| ## Citation | |
| If you find DFlash useful, please cite our work. To share feedback on DFlash or request new model support, please fill out this form: [DFlash Feedback](https://forms.gle/4YNwfqb4nJdqn6hq9). | |
| ```bibtex | |
| @article{chen2026dflash, | |
| title = {{DFlash: Block Diffusion for Flash Speculative Decoding}}, | |
| author = {Chen, Jian and Liang, Yesheng and Liu, Zhijian}, | |
| journal = {arXiv preprint arXiv:2602.06036}, | |
| year = {2026} | |
| } | |
| ``` |