Multi Step Processes medium
Why is Two-Phase Commit (2PC) generally avoided in modern high-scale microservices?
- A It is not supported by SQL databases.
- B It guarantees strong consistency.
- C It requires XML.
- D It is a 'Blocking' protocol. If the Coordinator crashes, resources are held indefinitely.
Answer: D. It is a 'Blocking' protocol. If the Coordinator crashes, resources are held indefinitely.
2PC trades Availability for Consistency. In a system with 100 services, if one service is slow, the 2PC lock blocks everyone. Sagas are preferred for availability.
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