User Guide¶
Operational documentation for deploying and configuring vLLM on Qualcomm Cloud AI hardware.
Software Stack¶
The Qualcomm Cloud AI SDK consists of two layers:
Platform SDK — driver support for Cloud AI accelerators, APIs for executing model binaries, and tools for card health, monitoring, and telemetry. Includes a kernel driver, userspace runtime with Python/C++ bindings, and card firmware.
Apps (Application) SDK — converts trained models and prepares runtime binaries for Cloud AI platforms. Contains the graph compiler, performance tuning tools, quantization support, and integration with QEfficient.
vLLM Integration¶
vllm-qaic connects vLLM to Qualcomm Cloud AI accelerators through a layered software stack — enabling any application built on the OpenAI API (LangChain, CrewAI, curl) to serve LLMs on Cloud AI hardware.
| Layer | Components | Description |
|---|---|---|
| Applications | curl, LangChain, OpenAI SDK | Any OpenAI-compatible client connects directly |
| vLLM Server | OpenAI-Compatible Endpoints | HTTP/gRPC serving with continuous batching and request scheduling |
| QAIC Backend | Prefill Engine, Decode Engine, KV Cache Manager, Sampler | vLLM backend dispatching to Cloud AI hardware |
| QEfficient / Apps SDK | ONNX Export, Quantization, Compiler (qaic-compile) |
One-time AOT compilation of HuggingFace models to QPC binaries |
| QPC | Compiled model binary | Static-shape binary optimized for Cloud AI execution |
| Cloud AI Accelerator | Multi-Card (Tensor Slicing), Disaggregated Serving (Prefill / Decode) | Hardware execution across one or more Cloud AI cards |
Two execution paths are supported:
AOT (Ahead-of-Time) — models are exported via QEfficient, compiled to a QPC binary by the QAIC compiler, and loaded at serve time. No PyTorch at runtime.
PYT (Eager) — models execute dynamically via the torch_qaic package, which registers Cloud AI as a PyTorch backend and dispatches operators to hardware.
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Support Matrix
Feature availability across AOT and Eager execution modes.
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Supported Models
20+ validated models across text, vision, embedding, and audio.
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Serving
Online API server (OpenAI-compatible) and offline batch inference.
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Features
Speculative decoding, quantization, multimodal, disaggregated serving, LoRA.
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Configuration
Engine arguments, environment variables, and device management.