Three Phase Commit
Three Phase Commit (3PC) is a distributed transaction protocol designed to improve fault tolerance over the traditional Two Phase Commit (2PC) by adding a pre-commit phase. It ensures atomicity in distributed systems, where multiple participants must agree to commit or abort a transaction, reducing the risk of blocking in case of coordinator failures. The protocol involves three phases: can-commit, pre-commit, and do-commit, allowing participants to make decisions independently if the coordinator crashes.
Developers should learn Three Phase Commit when building or maintaining distributed systems that require strong consistency and fault tolerance, such as distributed databases or microservices architectures with transactional guarantees. It is particularly useful in scenarios where coordinator failures are common, as it prevents indefinite blocking and allows participants to recover autonomously, though it adds complexity and latency compared to 2PC.