1.2.2. Impact of Transactions on the Journal

When transactions are used, a transaction ID (XID) is added to each record. The size of the XID is 24 bytes for local transactions. For distributed transactions, the user supplies the XID, which is usually obtained from the transaction monitor, and may be any size. In a transaction, in addition to message enqueue records, journal records are maintained for each message dequeue, and for each transaction abort or commit.