vllm-omni/recipes/SenseNova/SenseNova-U1.md

SenseNova-U1

Unified image generation and understanding

Summary

• Vendor: SenseNova
• Model: SenseNova/SenseNova-U1-8B-MoT
• Task: text2img, img2img, img2text (visual understanding), text2text (chat)
• Mode: Offline inference, Online serving (OpenAI-compatible API)
• Maintainer: Community

When to use this recipe

Use this recipe to run SenseNova-U1-8B-MoT via vLLM-Omni. SenseNova-U1 is a unified Qwen3-based LLM with Mixture-of-Tokenizers (MoT) attention that handles text encoding, optional chain-of-thought reasoning, flow-matching image denoising, and visual understanding in a single pipeline — no separate text encoder or VAE needed. It supports four task modalities: text-to-image, image-to-image editing (with dual CFG), image-to-text understanding, and text-to-text chat.

References

• Offline text-to-image: examples/offline_inference/text_to_image/text_to_image.py
• Offline image-to-image: examples/offline_inference/image_to_image/image_edit.py
• Online serving: examples/online_serving/sensenova_u1/
• E2E tests: tests/e2e/offline_inference/test_sensenova_u1_text2img.py, tests/e2e/offline_inference/test_sensenova_u1_img2img.py
• HuggingFace model page: SenseNova/SenseNova-U1-8B-MoT

Hardware Support

GPU

1x H200 (144GB)

Environment

• OS: Linux
• Python: 3.12
• Driver / runtime: NVIDIA 590.48.01, CUDA 13.1
• vLLM-Omni version: 0.18.1.dev

Command

python examples/offline_inference/text_to_image/text_to_image.py \
    --model SenseNova/SenseNova-U1-8B-MoT \
    --prompt "Close portrait of an elderly woman by a farmhouse window, textured skin, gentle smile, warm natural light, emotional documentary look. The portrait should feel polished and natural, with sharp eyes, realistic skin texture, accurate facial anatomy, and premium lighting that keeps the face as the main focus." \
    --width 1536 --height 2720 \
    --seed 42 --num-inference-steps 50 \
    --cfg-scale 4.0 \
    --extra-body '{"think": true, "cfg_norm": "none", "timestep_shift": 3.0, "t_eps": 0.02}' \
    --output outputs/sensenova_u1_output.png

Verification

pytest -s -v tests/e2e/offline_inference/test_sensenova_u1_text2img.py \
    -m "advanced_model" --run-level "advanced_model"

Notes

• E2E latency: 32.1s (1536×2720, 50 steps, think mode, CFG scale 4.0)
• Peak VRAM: 35.9 GB reserved, 35.1 GB allocated
• Model loading: 32.8 GiB, 8.7s
• No deploy YAML needed — the engine auto-generates a single-stage diffusion config.
• Think mode (--think) is recommended for higher image quality.

Text-to-Image via the shared example

SenseNova-U1 is registered with the shared text-to-image example. Forward SenseNova-specific generation parameters as a JSON object through --extra-body:

python examples/offline_inference/text_to_image/text_to_image.py \
    --model SenseNova/SenseNova-U1-8B-MoT \
    --prompt "A beautiful sunset over mountains" \
    --width 2048 --height 2048 \
    --num-inference-steps 50 \
    --seed 42 \
    --extra-body '{"think": true, "cfg_scale": 4.0, "cfg_norm": "none", "timestep_shift": 3.0, "t_eps": 0.02}' \
    --output sensenova_text2img.png

The --extra-body keys are filtered against the model's declared extra_body_params (see vllm_omni/model_extras/sensenova_u1.py): think, cfg_scale, cfg_norm, timestep_shift, t_eps, img_cfg_scale, and max_tokens. No deploy YAML is needed — the engine auto-generates a single-stage diffusion config.

Image-to-Image Editing (img2img)

python examples/offline_inference/image_to_image/image_edit.py \
    --model SenseNova/SenseNova-U1-8B-MoT \
    --prompt "Turn this into an oil painting" \
    --image input.png \
    --resolution 2048 \
    --seed 42 --num-inference-steps 50 \
    --cfg-scale 4.0 \
    --extra-args '{"think": true, "img_cfg_scale": 1.0, "cfg_norm": "none", "timestep_shift": 3.0}' \
    --output outputs/sensenova_u1_edit.png

• img2img uses dual CFG: --cfg-scale controls text guidance, while img_cfg_scale in --extra-args controls image guidance (1.0 = image CFG disabled).
• Pass multiple --image paths for multi-reference editing when the underlying pipeline supports them.

Image Understanding (img2text)

vllm serve SenseNova/SenseNova-U1-8B-MoT --omni --port 8091
python examples/online_serving/sensenova_u1/openai_chat_client.py \
    --prompt "Describe this image in detail" \
    --modality img2text \
    --image-url photo.jpg

Text-to-Text Chat (text2text)

vllm serve SenseNova/SenseNova-U1-8B-MoT --omni --port 8091
python examples/online_serving/sensenova_u1/openai_chat_client.py \
    --prompt "Explain the theory of relativity in simple terms" \
    --modality text2text

• For img2text and text2text, use the online chat-compatible example. The offline generic image examples intentionally focus on image-producing tasks.

2x H200 (144GB) — TP=2

Environment

• OS: Linux
• Python: 3.12
• Driver / runtime: NVIDIA 590.48.01, CUDA 13.1
• vLLM-Omni version: 0.18.1.dev

Command

python examples/offline_inference/text_to_image/text_to_image.py \
    --model SenseNova/SenseNova-U1-8B-MoT \
    --prompt "Close portrait of an elderly woman by a farmhouse window, textured skin, gentle smile, warm natural light, emotional documentary look. The portrait should feel polished and natural, with sharp eyes, realistic skin texture, accurate facial anatomy, and premium lighting that keeps the face as the main focus." \
    --width 1536 --height 2720 \
    --seed 42 --num-inference-steps 50 \
    --cfg-scale 4.0 \
    --extra-body '{"think": true, "cfg_norm": "none", "timestep_shift": 3.0, "t_eps": 0.02}' \
    --tensor-parallel-size 2 \
    --output outputs/sensenova_u1_output.png

Verification

Verify the output image is generated at outputs/sensenova_u1_output.png with the expected 1536×2720 resolution.

Notes

• E2E latency: 28.3s (1536×2720, 50 steps, think mode, CFG scale 4.0)
• Peak VRAM (per GPU): 18.2 GB reserved, 17.9 GB allocated
• Model loading: 16.5 GiB per GPU, 7.0s
• TP=2 provides ~12% speedup over TP=1; limited by serial CFG dual-forward and communication overhead.
• The LLM transformer uses QKVParallelLinear and MergedColumnParallelLinear for fused QKV and gate/up projections with TP support.

Online Serving

SenseNova-U1 supports all four modalities via the OpenAI-compatible /v1/chat/completions API.

Launch

vllm serve SenseNova/SenseNova-U1-8B-MoT --omni --port 8091

Send Requests

cd examples/online_serving/sensenova_u1

# Text-to-image
python openai_chat_client.py \
    --prompt "A beautiful sunset" --modality text2img

# Image-to-image editing
python openai_chat_client.py \
    --prompt "Turn this into an oil painting" \
    --modality img2img --image-url input.jpg

# Image understanding
python openai_chat_client.py \
    --prompt "Describe this image" \
    --modality img2text --image-url photo.jpg

# Text chat
python openai_chat_client.py \
    --prompt "What is the capital of France?" \
    --modality text2text

For full API documentation and curl examples, see examples/online_serving/sensenova_u1/README.md.