17.5. Two Phase Commit

The classical two-phase commit approach is the bedrock of JBoss Transaction Service, and more generally of Web Services transactions. Two-phase commit provides coordination of parties that are involved in a transaction. The general flow of a two-phase commit transaction is described in Figure 17.3, “Two-Phase Commit Overview”.
Two-Phase Commit Overview

Figure 17.3. Two-Phase Commit Overview


During two-phase commit transactions, coordinators and resources keep track of activity in non-volatile data stores so that they can recover in the case of a failure.