Purging Transaction Log Files

Any transaction log file is kept until TimesTen determines it can be purged. Under standard TimesTen operating conditions, unneeded transaction log files are purged each time a checkpoint is initiated.

A checkpoint can be initiated either through a configurable time interval with the CkptFrequency connection attribute or a configurable log volume with the CkptLogVolume connection attribute. In TimesTen, you can also initiate a checkpoint (either manually or in a background checkpointing application thread) with the ttCkpt built-in function.

If you are running out of file system space because of log files accumulating, use the CkptLogVolume connection attribute instead of the CkptFrequency connection attribute. In addition, you can tell if reclamation is blocked when frequently selecting from the SYS.V$LOG_HOLDS system view or calling the ttLogHolds built-in procedure.

Note:

To improve performance, locate your log files on a separate physical device from the one on which the checkpoint files are located. See Managing Transaction Log Buffers and Files.

See Checkpointing in the Oracle TimesTen In-Memory Database Introduction for general information on checkpointing. See Configuring or Turning Off Background Checkpointing for more details on CkptFrequency and CkptLogVolume connection attributes.

For more information on log holds, see SYS.V$LOG_HOLDS in the Oracle TimesTen In-Memory Database SQL Reference or ttLogHolds in the Oracle TimesTen In-Memory Database Reference.

See CkptFrequency, CkptLogVolume, and ttCkpt in the Oracle TimesTen In-Memory Database Reference.