Hidden Database Costs of an AI Rollout: Storage, CPU, Memory, and Cache

TL;DR
Adding RAG to your existing Postgres usually 5x’s the storage on the affected tables, drives the HNSW index off a memory cliff that doesn’t degrade gracefully, and pollutes the buffer cache hard enough that unrelated OLTP queries regress at p95. Halfvec, binary quantization with rerank, and a separate re...