Commit mode and sync level processing
The commit mode that you choose determines the type of commit mode processing that IMS performs.
The Java™ client specifies the commit mode protocol that is used when it submits a transaction
request to IMS. IMS Connect and IMS support two types
of commit mode processing:
- Commit mode 0 (commit-then-send), where IMS commits the IMS database changes and then sends the output to the client
- Commit mode 1 (send-then-commit), where IMS sends the output to the client and then commits the database changes
Associated with the commit mode protocols, IMS Connect and IMS also support three synchronization levels (sync levels):
NONE, CONFIRM, and SYNCPT (the sync-point protocol). All three sync levels can be used with
commit mode 1. Only CONFIRM can be used with commit mode 0. The Java client cannot explicitly
set the sync level to SYNCPT. The IMS TM resource adapter supports only the following combinations:
| Commit mode | Sync level = NONE supported | Sync level = CONFIRM supported |
|---|---|---|
| commit mode 0 | No | Yes |
| commit mode 1 | Yes | Yes |
Commit mode 1 with sync level SYNCPT is used by the IMS TM resource adapter when it participates in two-phase commit processing with IMS.