Processes in the Primary Replication Server

Learn how a transaction that originates in a primary data server is sent to the primary Replication Server and subsequently distributed to a replicate Replication Server.

• Replication Agent User Thread
  Learn how RepAgent and other Replication Agents work with Replication Server to distribute transaction information to subscribing replicate databases
• Stable Queue Manager Thread
  There is one Stable Queue Manager (SQM) thread for each stable queue accessed by the primary Replication Server, whether inbound or outbound. Each RepAgent user thread works with a dedicated SQM thread that reclaims stable queue space after a transaction is forwarded to a data server or to another Replication Server.
• Stable Queue Transaction Thread
  The Stable Queue Transaction (SQT) thread reassembles transactions and places the transactions in commit order.
• Distributor Thread and Related Modules
  For each primary database that is managed by an SAP Replication Server, the distributor (DIST) thread uses SQT to read from the inbound queue, and SQM threads to write transactions to the outbound queue.
• Distributor Status Recording
  Replication Server records the DIST status of a distributor thread in the Replication Server rs_databases system table in the RSSD
• Data Server Interface Threads
  Replication Server starts DSI threads to submit transactions to a replicate database to which it maintains a connection.
• Replication Server Interface Thread
  RSI threads are asynchronous interfaces to send messages from one Replication Server to another. One RSI thread exists for each destination Replication Server to which the source database has a direct route.
• Miscellaneous Daemon Threads
  There are several Replication Server daemon threads that perform miscellaneous tasks in the replication system.