checkpoint_completion_target
A parameter specifying how much time between checkpoints can be spent completing a checkpoint
checkpoint_completion_target is a configuration parameter specifying the fraction of the time between checkpoints which can elapse before a checkpoint is completed.
checkpoint_completion_target was added in PostgreSQL 8.3.
Usage
checkpoint_completion_target influences the "intensity" of I/O operations performed during a checkpoint. The more these can be spread out, the less risk there is of an I/O spike; consequently for a long time the general recommendation has been to set checkpoint_completion_target to 0.9 (the default from PostgreSQL 14) rather than the original default of 0.5.
Default value
The default value for checkpoint_completion_target is:
- PostgreSQL 14 ~:
0.9 - PostgreSQL 8.3 ~ PostgreSQL 13:
0.5
Change history
- PostgreSQL 14
- default value changed to
0.9(commit bbcc4eb2)
- default value changed to
- PostgreSQL 8.3
- added (commit 867e2c91)
References
- PostgreSQL documentation: checkpoint_completion_target