File
TimesTen databases are automatically persisted to disk storage using periodic checkpoints to keep snapshots of the database.
Checkpoint files contain an image of the database on disk.
TimesTen uses dual checkpoint files for additional safety, in case the system fails while a checkpoint operation is in progress.
Normal disk file systems are used for checkpoints.
TimesTen automatically performs background checkpoints based on the settings of the connection attributes:
- CkptFrequency
- and CkptLogVolume.
TimesTen also checkpoints the database when the last application disconnects. Applications can also checkpoint a database directly to disk by invoking the ttCkptBlocking built-in procedures described in the Oracle TimesTen In-Memory Database Reference.
Temporary databases are never fully checkpointed to disk, although Checkpoint operations can have significant overhead for permanent databases, depending on database size and activity, but have very little impact for temporary databases. Checkpoints are still necessary to remove transaction log files.