In order for an IMS/TM application program to function as a step of a global transaction, when defining the program and the corresponding transaction to IMS, on the APPLCTN macro definition, SCHDTYP must be set to PARALLEL. On the TRANSACT macro definition, PARLIM must be set to 0. For example:

APPLCTN  PSB=IWTEST10,PGMTYPE=TP,SCHDTYP=PARALLEL 
TRANSACT CODE=(IWT10,IWT10A,IWT10D,IWT10G),
      MODE=MULT,
      MSGTYPE=(MULTSEG,NONRESPONSE),
      PARLIM=0,
      PROCLIM=(65535,65535)

There must be sufficient message processing regions for all the steps of the global transactions. IMS locks the MPRs used for each step of the global transaction until the commit or rollback. A 30 step process flow would require at least 30 MPRs.

The CRM link to IMS must be configured with enough sessions. If a global transaction needs 30 MPRs to complete, it will need 30 sessions.

iWay Software