serving-llms-vllm

Deploy and optimize high-throughput LLM inference servers using vLLM with OpenAI-compatible APIs.

Updated Jul 3, 2026
One-click install
npx skills add https://github.com/CHENHUI-X/toolbox --skill serving-llms-vllm-chenhui-x
Or copy as Structured Prompt for Agent
Please help me install this Agent Skill.
Skill: serving-llms-vllm
Source: https://github.com/CHENHUI-X/toolbox/tree/main/custom-skills/inference/serving-llms-vllm
Command: npx skills add https://github.com/CHENHUI-X/toolbox --skill serving-llms-vllm-chenhui-x

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill requires vllm, torch, transformers, and includes references (resource) components.

What problem does it solve? Serving large language models in production is slow, memory-hungry, and hard to scale with naive transformers-based setups. This Skill guides you through deploying vLLM, which uses PagedAttention and continuous batching to achieve up to 24x higher throughput while fitting large models into limited GPU memory. ## Core Features & Use Cases - Production API Deployment: Launch OpenAI-compatible endpoints with tensor parallelism, prefix caching, and Prometheus metrics for monitoring TTFT and throughput. - Offline Batch Inference: Process large prompt datasets efficiently with automatic batching via the Python LLM engine API. - Quantized Model Serving: Fit 70B models on a single 40GB GPU using AWQ, GPTQ, or FP8 quantization with minimal accuracy loss. - Use Case: Deploy a Llama-3-70B chat API on 4x A100 GPUs with AWQ quantization, prefix caching, and load-tested throughput exceeding 100 requests per second. ## Quick Start Use the vLLM skill to help me deploy a Llama-3-8B model as an OpenAI-compatible API server on my GPU machine.

Frequently Asked Questions about serving-llms-vllm

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I deploy an LLM as an OpenAI-compatible API with vLLM?

Run 'vllm serve MODEL_NAME' to launch an OpenAI-compatible server on port 8000. Query it with the OpenAI Python SDK by setting base_url to http://localhost:8000/v1 and api_key to EMPTY.

How do I fit a 70B model on limited GPU memory?

Use AWQ or GPTQ quantization to reduce memory by roughly 4x, for example serving TheBloke/Llama-2-70B-AWQ with --quantization awq on a single 40GB GPU. Alternatively, split the model across multiple GPUs with --tensor-parallel-size.

vLLM vs TensorRT-LLM vs llama.cpp: which should I use?

Use vLLM for production multi-user APIs needing high throughput and broad hardware support. Choose TensorRT-LLM for maximum NVIDIA-only performance, llama.cpp for CPU or edge single-user inference, and HuggingFace transformers for research prototyping.

Why does vLLM run out of memory during model loading?

OOM occurs when the model plus KV cache exceeds available VRAM. Lower --gpu-memory-utilization to 0.7, reduce --max-model-len, enable AWQ quantization, or add GPUs with tensor parallelism.

How do I reduce time to first token in vLLM?

Enable prefix caching with --enable-prefix-caching for repeated prompt prefixes, and use --enable-chunked-prefill for long prompts. Reducing concurrent sequences with --max-num-seqs also prioritizes latency over throughput.

Does vLLM support monitoring and metrics in production?

Yes, vLLM exposes Prometheus metrics at the /metrics endpoint on the API port. Key metrics include vllm:time_to_first_token_seconds, vllm:num_requests_running, and vllm:gpu_cache_usage_perc, which integrate with Grafana dashboards.