Once the coordinator’s decision has been written to disk, the commit or abort request is sent to all participants. If this request fails or times out, the coordinator must retry forever until it succeeds. There is no more going back: if the decision was to commit, that decision must be enforced, no matter how many retries it takes. If a participant has crashed in the meantime, the transaction will be committed when it recovers—since the participant voted “yes,” it cannot refuse to commit when it recovers.

