PowerExchange extracts change data for DB2 tables registered for capture by reading journal entries from journal receivers. On busy systems, journal receivers can use a lot of disk storage space and need to be deleted at regular intervals.
Ensure that the journal receivers that are required for change data extraction are available to PowerExchange for read processing. Do not delete a journal receiver until the change data has been read from it and the restart tokens for the CDC sessions or PowerExchange Condense jobs no longer reference the receiver.
To control the deletion of journal receivers, you can use the CRTJRN (Create Journal) or CHGJRN (Change Journal) command to set the MNGRCV (Manage Receivers) and DLTRCV (Delete Receivers) attributes for the journals that are associated with the journal receivers. Informatica recommends the following settings:
MNGRCV(*SYSTEM)
DLTRCV(*NO)
If you specify DLTRCV(*YES), the journal receivers might be deleted during an IPL of the i5/OS server. In this case, PowerExchange CDC processing loses the entry that corresponds to the restart token.
Also, PowerExchange provides the following configuration options in the DBMOVER member in the CFG file to lock a journal receiver that it is processing and to notify you when that processing is complete:
AS4JRNEXIT
. Use this journal exit parameter on the AS4J CAPI_CONNECTION statement to prevent deletion of journal receivers from which PowerExchange is reading change data for DB2 tables registered for capture.
AS400EVENTMSGQ
. Use this parameter to specify a message queue to which to write the following messages related to journal processing:
If you specify AS4JRNEXIT=Y on the AS4J CAPI_CONNECTION statement, PowerExchange writes message DTL3001 to the message queue when PowerExchange finishes extracting change data from a journal receiver.
If you specify ALWCLRPFM=Y on the AS4J CAPI_CONNECTION statement, PowerExchange writes message DTL3002 to the message queue if a journal entry for a CLRPFM command is encountered. PowerExchange cannot replicate changes that result from a CLRPFM command.