AI inference glossary
Software

Mooncake Store

Also known as Mooncake, Mooncake KV store, P2P KV pooling

In plain English

Mooncake Store pools the host memory and NVMe drives across many servers into one shared KV-cache store that any accelerator in the cluster can read.

Technical definition

Mooncake Store is the open-source distributed KV-cache storage layer from the Mooncake project that aggregates DRAM and NVMe across serving nodes into a single logical pool with peer-to-peer access.

Engineering details

With P2P pooling, the KV-cache storage on each host is presented as one logical memory pool, so an accelerator on any server can fetch cache written by any other server instead of only its own host. Mooncake Store also pools NVMe across servers and supports distributed filesystem backends such as WEKA and VAST. It is used with vLLM and SGLang on GPUs as the industry-standard offloading store, and Google is adding TPU support along with the DRAM P2P pooling mode, likely implemented on TPU-Sync primitives.

Why it matters

Agentic and multi-turn workloads reuse long prefixes across many requests and across sub-agent bursts. A cluster-wide pool raises the KV-cache hit rate well beyond what a single host’s DRAM allows, which is what makes high-concurrency agent serving economical once HBM is exhausted.

How to read it in InferenceX

AgentX results on GPUs already depend on offloading behavior, and the planned AgentX TPU results will exercise Mooncake Store and TPU-Sync on Ironwood. The InferenceX Official Preview lists Mooncake support as one of the next externalization steps after disaggregation.