Transaction retry characteristics

IMS retries certain abend conditions.

These retry conditions still apply to standard DL/I application programs even if they receive their messages from an LU 6.2 application program. If an abend that can be retried occurs, IMS issues an APPC ATBEXAI call to APPC/MVS to determine if any established conversations exist. If a conversation has been allocated, the abend is not retried and the application program is terminated.

If any CPI Communications resource is being used by the application program, the abend condition cannot be retried. Thus, CPI Communications driven application programs and modified IMS application programs that have allocated an LU 6.2 conversation before the abend occurred can never be retried. This prohibition on retry is necessary, because IMS cannot control the state of CPI Communications resources. IMS supports the DL/I INIT STATUS GROUPB call for CPI Communications driven application programs, but not for modified IMS application programs that have allocated an LU 6.2 conversation before the deadlock is detected.