AI inference glossary
Software

llm-d

Also known as llm-d project, Kubernetes LLM serving, distributed inference orchestrator

In plain English

llm-d is a Kubernetes-native framework that runs vLLM across many nodes with smart routing, prefix-aware scheduling, and disaggregated prefill and decode.

Technical definition

llm-d is an open-source distributed inference serving framework built on Kubernetes and vLLM that provides KV-aware routing, prefill-decode disaggregation, and multi-node scheduling for large model deployments.

Engineering details

A single vLLM instance serves one replica. Production deployments need a layer that routes each request to the replica most likely to hold its prefix in cache, splits prefill and decode across separate pools, and scales those pools independently. llm-d supplies that orchestration, backed by Red Hat, Google, and other contributors. TPU support in llm-d is part of Google’s externalization work for prefill-decode disaggregation, alongside the TPU-Sync transfer library, so external TPU customers can run the same disaggregated topology Google uses internally for Gemini.

Why it matters

Disaggregation and KV-aware routing are where much of the remaining performance-per-dollar gain sits for TPU, and they only exist above the engine. Shipping TPU support in a widely used orchestrator matters as much as the engine backend for making those features usable outside Google.

How to read it in InferenceX

InferenceX single-node aggregated results do not exercise llm-d. The planned TPUv7 disaggregated comparison against GB200 and GB300 NVL72 depends on the llm-d and TPU-Sync work landing in the external stack.