Scaling RAG to very large knowledge bases
We can scale RAG using a hierarchical system. A hierarchical RAG system is an advanced architecture that organizes document retrieval in a tree-like structure with multiple levels. Instead of searching through all documents linearly, it first clusters similar documents together and creates a hierarchy of these clusters. When a query comes in, the system identifies the most relevant cluster(s) at the top level, drills down to find the most relevant sub-clusters, and finally retrieves the most similar documents from within those targeted sub-clusters. Think of it like a library where books are first organized by broad categories (science, history, fiction), then by sub-categories (physics, biology, chemistry), and finally by specific topics – this makes finding a particular book much faster than searching through every single book.
The hierarchical approach to RAG offers significant advantages because it dramatically improves both the...