Shipment tracking: reporting reads crowding the primary

A logistics company runs shipment tracking on one Amazon RDS for PostgreSQL DB instance that also answers a fast-growing analyst reporting workload.

Reporting queries now hold the instance above 90 percent CPU for most of the afternoon, tracking updates queue behind them, and the instance already runs on the largest class in its family.

Reports may read data a few seconds behind the primary, but every insert and update has to keep landing on the primary, and the team cannot change the relational schema or the SQL the reports already run.

A two-person platform team owns the database, so the change must ship in one sprint and must not add application code they then have to maintain.