2. Two-Phase Commit
Two phase commit (2PC) is the standard protocol for making commit and abort atomic
Coordinator - the component that coordinates commitment at home(T)
Participant - a resource manager accessed by T
A participant P is ready to commit T if all of T’s after-images at P are in stable storage
The coordinator must not commit T until all participants are ready
- If P isn’t ready, T commits, and P fails, then P can’t commit when it recovers.