Connection Pools: Size Them for the Database
Adding more application workers can exhaust database connections rather than improve throughput. This guide gives you a small, testable way to approach the issue before changing a live system.
A practical workflow
- Count the maximum connections from every service instance and leave headroom for maintenance.
- Start with a modest pool, measure wait time, transaction duration and server CPU under realistic load.
What to check
A pool cannot rescue slow queries or transactions held open while waiting on external services. Compare the result with the original problem and record what changed. If a measurement or test does not support the change, revisit the assumption rather than adding more complexity.
Keep the experiment small enough to reverse. Document the starting state, the change and the result so another person can repeat the process. Product menus and versions can change, so check the current documentation for your environment.
Official reference: Read the documentation.