Local units of work

Units of work that involve only the queue manager are called local units of work. Syncpoint coordination is provided by the queue manager itself (internal coordination) using a single-phase commit process.

To start a local unit of work, the application issues MQGET, MQPUT, or MQPUT1 requests specifying the appropriate syncpoint option. The unit of work is committed using MQCMIT or rolled back using MQBACK. However, the unit of work also ends when the connection between the application and the queue manager is broken, intentionally or unintentionally.

If an application disconnects (MQDISC) from a queue manager while a global unit of work coordinated by IBM MQ is still active, an attempt is made to commit the unit of work. If, however, the application terminates without disconnecting, the unit of work is rolled back as the application is deemed to have terminated abnormally.