CPU resource requirements

CDC Replication source and target systems both require CPU resources and the availability of CPU directly affects the number of rows processed and the general performance of the product. CPU resources are consumed by different processes on the source and target systems.

CPU resources are consumed by different processes on the source and target systems. The following table lists CPU resource consumption for source and target systems by replication engine.
Replication engine Source system CPU resources are required for these processes: Target system CPU resources are required for these processes:
  • CDC Replication Engine for Db2® Database
  • CDC Replication Engine for Microsoft SQL Server
  • CDC Replication Engine for Oracle databases
  • Capturing, decoding, and staging the changed data stored in the database log files. The product must process and filter the entire database log at all times, even if the majority of the log contains out-of-scope data.
  • Transmitting the captured change data to the target system using TCP/IP.
  • Refresh operations which query the database directly using JDBC.
  • Querying the database directly for replication and refresh of LOB and LONG data types.
  • Microsoft SQL Server: Querying the database directly for replication and refresh of LOB, CLOB, XML, and SQL_VARIANT data types.
  • Querying the database directly for %GETCOL functions.
  • Receiving captured change data from the source system.
  • Conversion of the captured change data to database operations.
  • Committing the database operations to the target database.
  • Execution of SQL operations by the target database during the apply process on the target system.
  • Multiple indexes on tables in the target database often requires additional CPU resources.
CDC Replication Engine for InfoSphere® DataStage®

CDC Replication Engine for InfoSphere DataStage can only be deployed as a target of replication and is not available as a source of replication.

  • Receiving captured change data from the source system.
  • Generating and writing flat files to disk.
CDC Replication Engine for Db2 for z/OS®
  • Capturing, decoding, and staging the changed data stored in the database log files. The product must process all records from the DB2® log for Units of Recovery and records for tables which have DATA CAPTURE CHANGES configured. The DB2 IFI interface must filter the entire database log at all times, even if the majority of the log contains out-of-scope data.
  • Transmitting the captured change data to the target system using TCP/IP.
  • Querying the database directly for %GETCOL or %SELECT functions.
  • Receiving captured change data from the source system.
  • Conversion of the captured change data to database operations.
  • Committing the database operations to the target database.
  • Execution of SQL operations by the target database during the apply process on the target system.
  • Multiple indexes on tables in the target database often requires additional CPU resources.
  • Code page conversion