Syncpoints in WebSphere MQ for Windows, WebSphere MQ for iSeries, and WebSphere MQ on UNIX systems

 

Syncpoint support operates on two types of units of work: local and global.

A local unit of work is one in which the only resources updated are those of the WebSphere MQ queue manager. Here syncpoint coordination is provided by the queue manager itself using a single-phase commit procedure.

A global unit of work is one in which resources belonging to other resource managers, such as databases, are also updated. WebSphere MQ can coordinate such units of work itself. They can also be coordinated by an external commitment controller such as another transaction manager or the i5/OS commitment controller.

For full integrity, use a two-phase commit procedure. Two-phase commit can be provided by XA-compliant transaction managers and databases such as IBM's TXSeries and UDB and also by the i5/OS commitment controller. WebSphere MQ products (except WebSphere MQ for iSeries and WebSphere MQ for z/OS) can coordinate global units of work using a two-phase commit process. WebSphere MQ for iSeries can act as a resource manager for global units of work within a WebSphere Application Server environment, but cannot act as a transaction manager.

• Local units of work
  

• Global units of work
  

• Interfaces to external syncpoint managers
  

 

Parent topic:

Committing and backing out units of work

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