Post-Log Merge does not degrade the performance of the change data capture process. Each ECCR connects to the member PowerExchange Logger for z/OS on the local z/OS system to pass captured changes to the Logger.

During change data extraction, if the member Logger or the z/OS system on which the member Logger resides is running slowly, the log-merge processing that the Post-Log Merge task performs for the log readers might be degraded. The change extraction process must wait until the Post-Log Merge task merges the change data from the all member Loggers on the z/OS systems, including the slowest Logger or slowest system, and present the change records in the proper chronological order.

The Post-Log Merge task reads change records from the active log data set of each member Logger as the records are written. You can tune Post-Log Merge performance in the following ways: