What is a Checkpoint? What does Checkpoint Process (CKPT) do?

[dtech-team]

The checkpoint process is responsible for updating file headers in the database datafiles. A checkpoint occurs when Oracle moves new or updated blocks (called dirty blocks) from the RAM buffer cache to the database datafiles.

A checkpoint keeps the database buffer cache and the database datafiles synchronized. This synchronization is part of the mechanism that Oracle uses to ensure that your database can always be recovered.

Source: http://www.dba-oracle.com

[dtech-team]

When a checkpoint occurs, Oracle must update the headers of all datafiles to record the details of the checkpoint. This is done by the CKPT process. The CKPT process does not write blocks to disk; DBWn always performs that work.

The statistic DBWR checkpoints displayed by the System_Statistics monitor in Enterprise Manager indicates the number of checkpoint requests completed.

SOURCE: http://www.stanford.edu