What It does
Synchronizes the Modified DataBlocks in Memory with the Blocks in the datafiles (disk) -Done by DBWR.
The CKPT process updates the Header of all datafiles with the latest SCN (Not on Read only Tablespace).
When It Happens
- When " ALTER SYSTEM CHECKPOINT" issued.
- When "ALTER SYSTEM SWITCH LOGFILE" issued.
- During each Log Switch.
- LOG_CHECKPOINT_TIMEOUT is reached
- LOG_CHECKPOINT_INTERVAL*Size of IO OS Block -reached.
Enabling the LOG_CHECKPOINTS_TO_ALERT ,makes the entry in the ALERT log with Timestamp for each checkpoint.
