RMAN Fast incremental backup-(Block change tracking) Block tracking function

The Block change tracking process records changes in data blocks since the last level 0 backup and records this information in a trace file.

RMAN uses this file to determine the change data that needs to be backed up in an incremental backup; it greatly improves the backup performance and speed, and RMAN can no longer scan the entire file to find the change data.

Check to see if fast tracking is on

SQL > col FILENAME for A20

SQL > select * from v$block_change_tracking

STATUS FILENAME BYTES

DISABLED

SQL >

SQL > select name from v$asm_diskgroup

NAME

-

DATA

OCR

SQL >

Turn on block tracking function

SQL > alter database enable block change tracking using file'+ DATA'

Database altered.

SQL > select status,filename,bytes/1024/1024 M from v$block_change_tracking

STATUS FILENAME M

ENABLED + DATA/test11g/change 11.0625

Tracking/ctf.350.984

678355

SQL >

Turn off the block tracking function, and the block modification tracking file will be deleted.

SQL > alter database disable block change tracking

Database altered.

SQL >

SQL > select status,filename,bytes/1024/1024 M from v$block_change_tracking

STATUS FILENAME M

DISABLED

SQL >