linkend="guc-checkpoint-segments"> log segments, or every <xref
linkend="guc-checkpoint-timeout"> seconds, whichever comes first.
The default settings are 3 segments and 300 seconds (5 minutes), respectively.
- In cases where little or no WAL has been written, checkpoints will be
- skipped even if checkpoint_timeout has passed. At least one new WAL segment
- must have been created before an automatic checkpoint occurs. The time
- between checkpoints and when new WAL segments are created are not related
- in any other way. If file-based WAL shipping is being used and you want to
- bound how often files are sent to standby server to reduce potential data
+ In cases where no WAL has been written since the previous checkpoint, new
+ checkpoints will be skipped even if checkpoint_timeout has passed.
+ If WAL archiving is being used and you want to put a lower limit on
+ how often files are archived in order to bound potential data
loss, you should adjust archive_timeout parameter rather than the checkpoint
parameters. It is also possible to force a checkpoint by using the SQL
command <command>CHECKPOINT</command>.