Show Table of Contents
9.3.2. About the LRCO Optimization for Single-phase Commit (1PC)
Although the 2-phase commit protocol (2PC) is more commonly encountered with transactions, some situations do not require, or cannot accommodate, both phases. In these cases, you can use the single phase commit (1PC) protocol. One situation where this might happen is when a non-XA-aware datasource needs to participate in the transaction.
In these situations, an optimization known as the Last Resource Commit Optimization (LRCO) is employed. The single-phase resource is processed last in the prepare phase of the transaction, and an attempt is made to commit it. If the commit succeeds, the transaction log is written and the remaining resources go through the 2PC. If the last resource fails to commit, the transaction is rolled back.
While this protocol allows for most transactions to complete normally, certain types of error can cause an inconsistent transaction outcome. Therefore, use this approach only as a last resort.
Where a single local TX datasource is used in a transaction, the LRCO is automatically applied to it.
Where did the comment section go?
Red Hat's documentation publication system recently went through an upgrade to enable speedier, more mobile-friendly content. We decided to re-evaluate our commenting platform to ensure that it meets your expectations and serves as an optimal feedback mechanism. During this redesign, we invite your input on providing feedback on Red Hat documentation via the discussion platform.