Commitment definitions for two-phase commitment control

 

To change the commitment options for your transaction after you start commitment control, use the Change Commitment Options (QTNCHGCO) API.

Depending on your environment and your applications, changing the commitment options can improve your system's performance.

If you are using a DRDA^® distributed unit of work over TCP/IP connection, the only option that applies is Allow vote read-only.

• Commitment definition for two-phase commit: Allow vote read-only
  Normally, a transaction manager participates in both phases of commit processing. To improve the performance of commit processing, you can set up some or all locations in a transaction to allow the transaction manager to vote read-only.

• Commitment definition for two-phase commit: Not wait for outcome
  When a communication or system failure occurs during a commit operation so that resynchronization is required, the default is to wait until the resynchronization is finished before the commit operation completes.

• Commitment definition for two-phase commit: Indicate OK to leave out
  Normally, the transaction manager at every location in the transaction program network participates in every commit or rollback operation. To improve performance, you can set up some or all locations in a transaction to allow the transaction manager to indicate OK to leave out.

• Commitment definition for two-phase commit: Not select a last agent
  By default, the transaction manager for the initiator is free to select any agent as a last agent during a commit operation.

• Vote reliable effect on flow of commit processing
  Vote reliable is an optimization that improves performance by returning earlier to the initiator application after a commit operation and eliminating one message during a commit operation.

 

Parent topic:

Two-phase commitment control

 

Related reference

Change Commitment Options (QTNCHGCO) API