Vector Storage in RAG - Choosing the Right Backend [Coming Soon...]

Selecting vector storage is not just a database decision. It is an operational decision.

This comparison focuses on four dimensions: latency, cost, security, and multitenancy.

RDS-based patterns

• Good transactional control and governance.
• Predictable operational model for SQL-heavy teams.
• May require careful indexing strategy under high retrieval concurrency.

S3-based patterns

• Low-cost storage and high durability.
• Useful for batched or offline retrieval workflows.
• Requires additional orchestration for low-latency serving paths.

OpenSearch-based patterns

• Strong query flexibility and integrated observability tooling.
• Useful when search analytics and retrieval debugging matter.
• Cost and scaling behavior need active tuning.

Practical rollout sequence

1. Deploy baseline to local clusters (Minikube).
2. Add OpenSearch logging for retrieval traces.
3. Run backend variations (RDS, S3, OpenSearch).
4. Validate cloud deployment path (including Bedrock model routing where applicable).

The best option is the one your team can operate reliably under real load.