On z/OS, the IMS capture agents and the VSAM capture write data to z/OS System Log Streams (zLog). Log Streams are high performance file systems managed by z/OS that provides functionality similar to the CDCStore Storage Agent.
The zLog Publisher distributes captured data to downstream Engines and performs Log Stream cleanup. Together, z/OS Log Streams and the zLog Publisher provide benefits beyond ordinary messaging frameworks because multiple target engines utilize the same captured data without requiring its duplication. The ability to manage both transient and longer term storage provides efficiency and flexibility. Target engines need not operate on the same schedule or at the same performance level. Generally however, all subscribing target engines should be operational allowing Log Streams to be cleaned and storage resources re-used.
There are two zLOGC diagnostic procedures used to identify performance problems. For more information, refer to the Diagnostic Tools and Options section.