Scaling Reads medium
Why does opening a new database connection for every single HTTP request kill performance at scale?
- A It uses too much bandwidth.
- B The TCP Handshake + Authentication handshake takes time (latency) and consumes CPU/RAM on the DB server.
- C Databases only allow 10 connections total.
- D It is not secure.
Answer: B. The TCP Handshake + Authentication handshake takes time (latency) and consumes CPU/RAM on the DB server.
Connection Pooling maintains a set of open, ready-to-use connections. Reusing them is much faster than establishing a new one (which is expensive).
One system design question a day, with spaced repetition so the ones you miss come back.
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