Oracle 12c provides block change tracking to increase performance of incremental backups by recording change blocks for each datafile, thus stopping RMAN from scanning each datafile to determine changes.   This feature must be enabled by default it is disabled in the database.  Tracking information on each changed block is stored in a file located in the directory defined by parameter DB_CREATE_FILE_DEST and is only used by level 1 backups.   Additionally, the tracking must be enabled before the level 0 backup is performed in order for level 1 backups to use it.   Use ALTER DATABASE command to turn on Block Change Tracking:

 

ALTER DATABASE ENABLE BLOCK CHANGE TRACKING;

 

You can also specify the location of the tracking file:

 

ALTER DATABASE ENABLE BLOCK CHANGE TRACKING USING FILE ‘/linux1/rman_change_tracking.file’  REUSE;

 

Disable Block tracking with:

 

ALTER DATABASE DISABLE BLOCK CHANGE TRACKING;

 

 

Larry Catt

OCP