by Amit Shekhar · 21 June 2026
How does an Embedding Cache work?
How an Embedding Cache works. We will also see what an embedding is, why an Embedding Cache saves us a lot of money and time, how the cache key is built, and where it is used in real systems like RAG and semantic search.
Read on Outcome School ↗then come back to lock it in
Before you read, guessWhy is it beneficial to cache embeddings rather than computing them on every request?
Ten seconds, a guess, then read — a wrong guess still makes the answer stick.
What this article covers
- What is an embedding
- A quick recap of how we get an embedding
- What is an Embedding Cache
- Why we need an Embedding Cache
- The core idea behind an Embedding Cache
- The cache key, a hash of the text plus the model
- The request flow, a hit and a miss
- Eviction, LRU and TTL
- Where the cache lives, memory or disk
- The benefits of an Embedding Cache
- An Embedding Cache in the real world
The article lives on outcomeschool.com. Read it there, then come back: the tutor in the margin has read it and will answer questions, and the questions below check what stayed.