Sections
IntroductionOrientation01 · Why Inference Servers Exist02 · Where vLLM Sits03 · Anatomy of a vLLM SetupStage 1 — Core Concepts01 · The KV Cache02 · Prefill vs Decode03 · PagedAttention04 · Continuous Batching05 · Sampling ParametersStage 2 — The Engine01 · The Scheduler & Block Manager02 · Lifecycle of a Request03 · Prefix Caching04 · Quantisation05 · Speculative DecodingStage 3 — Running It Locally01 · Installing vLLM02 · Offline Batch Inference03 · The OpenAI-Compatible Server04 · Streaming & Client Patterns05 · The Getting-Started NotebookStage 7 — Case Studies01 · RAG Chatbot at Scale02 · Offline Batch Summarisation03 · Coding Agent on Long Context04 · Multi-Tenant LoRA on One GPU
Orientation
2 min read
You can explain what an inference server does that a model.generate() loop doesn't, and say out
loud why you're choosing vLLM. · ~2 days
Nothing in this stage requires a GPU. It's the stage where you build the mental model that makes every flag in Stage 4 obvious instead of arbitrary — and, just as usefully, the stage where you learn the three situations in which the honest answer is "don't use vLLM."
The one idea to carry out of here: an inference server is not a faster model. It is a scheduler and a memory allocator wrapped around the same weights. Everything else follows from that.
Pages
| # | Topic | What it covers | Status |
|---|---|---|---|
| 1 | Why Inference Servers Exist | The naive serving loop and its five failures; static batching; KV cache waste; the throughput-versus-latency trade-off stated precisely | 🚧 |
| 2 | Where vLLM Sits | vLLM against TGI, TensorRT-LLM, SGLang, llama.cpp and Ollama; what vLLM optimises for; the three situations where it's the wrong choice | 🚧 |
| 3 | Anatomy of a vLLM Setup | Engine versus server; what pip install vllm actually pulls in; where model weights live; the GPU, driver and CUDA prerequisites, honestly stated |
🚧 |
What you need to have working by the end
- A Python 3.10+ environment, local or Colab.
- Either a GPU you can reach, or a Colab account — the free T4 tier is enough for everything in Stages 0–3.
- Nothing installed yet. Installing vLLM is
deliberately in Stage 3, because installing a tool before you know what it does is how people end
up with a
--gpu-memory-utilizationvalue they can't defend.
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