Comet Lab Atlas

An open-source vector database built for billion-scale similarity search.

Milvus is a vector database engineered for scale: distributed architecture, multiple index types, and the ability to handle billions of vectors with high query throughput.

That power comes with operational weight — it is a real distributed system — which is justified when the scale genuinely demands it.

Where it's ideally used

A fit when vector search must operate at very large scale, into the billions of vectors.

Where it doesn't fit

Operationally heavy — overkill for the small and medium workloads that most RAG projects actually have.