sglang-xpu-bench

sglang-xpu-bench

sglang.bench_serving is SGLang's online benchmark client (the counterpart to vllm bench serve). Speaks the OpenAI-compatible API exposed by sglang-xpu-run.

Step 0 — verify SGLang server is running on Intel XPU

REQUIRED: Before benchmarking, you must confirm a SGLang server is running, identify its port, and verify it's using Intel XPU (not CPU fallback, not NVIDIA). This prevents benchmarking a server that silently fell back to CPU.

Run the checks below in a single shell session (later blocks reuse $SGLANG_PID, $SGLANG_PORT, $MODEL from earlier ones).

Find the server process and its container:

# 1. Check if SGLang is running and find its container
SGLANG_PID=$(ps aux | grep -iE 'sglang|launch_server' | grep -v grep | awk 'NR==1 {print $2}')
if [ -z "$SGLANG_PID" ]; then
    echo "❌ No SGLang server found running. Start one with sglang-xpu-run."
    exit 1
fi
echo "✓ SGLang server found (PID: $SGLANG_PID)"

CONTAINER_NAME=$(docker ps --format '{{.Names}}' 2>/dev/null | while read name; do
    if docker top "$name" -o pid 2>/dev/null | awk 'NR>1' | grep -qxF "$SGLANG_PID"; then echo "$name"; break; fi
done)
if [ -z "$CONTAINER_NAME" ]; then
    echo "❌ No container matched PID $SGLANG_PID. This skill runs the bench client"
    echo "   via 'docker exec' because the sglang package is only installed inside"
    echo "   the server container. A host-only SGLang install is not supported here."
    exit 1
fi
echo "✓ SGLang container: $CONTAINER_NAME"

Read the launch args once — they give you both the container-internal port and the --device flag. The bench client runs via docker exec inside the container, so the port must be the one SGLang binds inside the container (host ss can't see the container-namespaced socket). The --device xpu check is REQUIRED — it catches a server that silently fell back to CPU:

# 2. Read port + device from the launch args in one pass (REQUIRED)
ARGS=$(ps -p "$SGLANG_PID" -o args=)
SGLANG_PORT=$(echo "$ARGS" | awk '{for(i=1;i<=NF;i++) if($i=="--port" && i<NF) print $(i+1)}' | head -1)
SGLANG_PORT=${SGLANG_PORT:-30000}   # sglang default
DEVICE_ARG=$(echo "$ARGS" | awk '{for(i=1;i<=NF;i++) if($i=="--device" && i<NF) print $(i+1)}' | head -1)
echo "DEVICE_ARG=${DEVICE_ARG:-none}"
if [ "$DEVICE_ARG" = "cuda" ]; then
    echo "❌ Server is on NVIDIA CUDA, not Intel XPU."; exit 1
elif [ "$DEVICE_ARG" = "xpu" ]; then
    echo "✓ SGLang server has --device xpu"
else
    echo "⚠️  Could not confirm --device xpu (got: '${DEVICE_ARG:-none}'); relying on XPU memory check."
fi

# 3. Verify reachable from inside the container and read model name
if ! docker exec "$CONTAINER_NAME" curl -s http://127.0.0.1:$SGLANG_PORT/v1/models >/dev/null 2>&1; then
    echo "❌ SGLang server not responding on container port $SGLANG_PORT."
    exit 1
fi
MODEL=$(docker exec "$CONTAINER_NAME" curl -s http://127.0.0.1:$SGLANG_PORT/v1/models | python3 -c "import sys,json; print(json.load(sys.stdin)['data'][0]['id'])")
echo "✓ Responding on container port $SGLANG_PORT — model: $MODEL"