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Introduction

Qwen3-8B is a compact dense model in the Qwen3 series developed by Alibaba, featuring 8B parameters with Grouped-Query Attention (GQA) and up to 128K context length. It delivers significant improvements in instruction following, logical reasoning, text comprehension, mathematics, science, coding, and tool usage. The model supports EAGLE3 speculative decoding for accelerated inference and is available in both standard and thinking/reasoning-enhanced editions. This document demonstrates the deployment of Qwen3-8B on Ascend NPUs using SGLang, including single-node PD mixed mode, feature configuration, and performance optimization. This document is validated and written based on SGLang v0.5.13. The current model (Qwen3-8B) is fully supported in this version. To use the latest features (e.g., speculative decoding), it is recommended to use v0.5.13 or a later version.

Supported features

FeatureExample usage
Tensor Parallelism--tp-size 2
Quantization--quantization modelslim
Chunked Prefillauto based on device memory, or set explicit value;
disable with --chunked-prefill-size -1; e.g. --chunked-prefill-size 8192
NPU Graphenabled by default; disable with --disable-cuda-graph;
control range via --cuda-graph-bs or --cuda-graph-max-bs; e.g. --cuda-graph-bs 1 2 4 6 9 10 15 16
Speculative Decoding--speculative-algorithm EAGLE3 \
--speculative-draft-model-path /path/to/draft-model-weights \
--speculative-num-steps 3 \
--speculative-eagle-topk 1 \
--speculative-num-draft-tokens 4 \
--speculative-draft-model-quantization unquant
Overlap Scheduleexport SGLANG_ENABLE_OVERLAP_PLAN_STREAM=1
The values in the Example usage column are for illustration only. Adjust them according to your hardware, deployment mode, and workload. For parameter details, see Feature descriptions; for recommended configurations for each deployment scenario, see Best practices.
For feature compatibility and conflict information between features, see Feature Compatibility.

Prerequisites

Model weights

If you need to download model weights, check the model size before downloading to reserve enough space.
Ensure the available device memory exceeds the model weight size before deployment. For optimal throughput and latency, refer to the best practice configurations which may require additional cards. It is recommended to download the model weights to a shared directory across multiple nodes.

Installation

Ensure sufficient disk space before pulling images. The Docker image requires at least 30 GB of free space.
The dependencies required for the NPU runtime environment have been integrated into a Docker image and uploaded to the online platform. You can directly pull it. Both stable releases and daily builds are available. The following command is based on the stable release tag. For details, see Docker image versions.
Command
docker pull quay.io/ascend/sglang:v0.5.13.post1-cann9.0.0-a3

docker run -itd --shm-size=16g --name ${NAME} \
--privileged=true --net=host \
-v /var/queue_schedule:/var/queue_schedule \
-v /etc/ascend_install.info:/etc/ascend_install.info \
-v /usr/local/sbin:/usr/local/sbin \
-v /usr/local/Ascend/driver:/usr/local/Ascend/driver \
-v /usr/local/Ascend/firmware:/usr/local/Ascend/firmware \
--device=/dev/davinci0:/dev/davinci0  \
--device=/dev/davinci1:/dev/davinci1  \
--device=/dev/davinci2:/dev/davinci2  \
--device=/dev/davinci3:/dev/davinci3  \
--device=/dev/davinci4:/dev/davinci4  \
--device=/dev/davinci5:/dev/davinci5  \
--device=/dev/davinci6:/dev/davinci6  \
--device=/dev/davinci7:/dev/davinci7  \
--device=/dev/davinci8:/dev/davinci8  \
--device=/dev/davinci9:/dev/davinci9  \
--device=/dev/davinci10:/dev/davinci10  \
--device=/dev/davinci11:/dev/davinci11  \
--device=/dev/davinci12:/dev/davinci12  \
--device=/dev/davinci13:/dev/davinci13  \
--device=/dev/davinci14:/dev/davinci14  \
--device=/dev/davinci15:/dev/davinci15  \
--device=/dev/davinci_manager:/dev/davinci_manager \
--device=/dev/hisi_hdc:/dev/hisi_hdc \
--entrypoint=bash \
quay.io/ascend/sglang:v0.5.13.post1-cann9.0.0-a3
  • If the model weights have already been downloaded to a shared directory, use -v to mount the model path into the container, for example: -v /path/to/models:/models.
  • Replace ${NAME} with your own container name or remove --name to use default name.

Online service deployment

Single-node online deployment

Single-node deployment completes both prefill and decode within the same node (PD mixed mode), suitable for scenarios with limited hardware resources. This scenario is already covered in the best practice. For the complete, optimized deployment commands and benchmark data, see Qwen3-8B Best Practice — PD Mixed On A3.

Functional verification

After the service is started, you can invoke the model by sending a prompt:
# ============================================================
# Before running, update the following variables:
#   HOST: the server host address (e.g., localhost)
#   PORT: the server port number (e.g., 6688)
# ============================================================

curl http://${HOST}:${PORT}/generate \
    -H "Content-Type: application/json" \
    -d '{
        "text": "What is the capital of France?",
        "sampling_params": {
            "max_new_tokens": 64,
            "temperature": 0
        }
    }'
Expected result: an HTTP 200 response with the generated text containing “Paris”. Once the server prints The server is fired up and ready to roll! in the logs, it is ready to accept requests. For more testing examples (Health Check, Generate, Chat Completions, and port usage guidance), see Testing the Service.

Accuracy evaluation

For accuracy evaluation methods and datasets, see Accuracy Evaluation on Ascend NPU.

Performance

For performance data and benchmark commands, see Performance Testing on Ascend NPU.

Best practices

Best practice configuration reference

For complete optimal configurations with deployment scripts and benchmark commands, see the Qwen3-8B Best Practice page.

Performance tuning

For the full list of supported features, see Supported features. For detailed optimization guidance, see Optimization on Ascend NPU.

FAQ

For common environment, installation, and general parameter issues, please refer to the Ascend NPU FAQ. This section only covers model-specific issues.