Logsender not connected to stone risks transmitting incomplete tranlog records
In a hotstandby system, when the logsender is not connected to the master Stone, the logsender relies on disk file information to check for when a transaction log record is ready to send to the logreceiver.
However, logical tranlog records may cross a file system block boundary, and this not detected by the logsender’s disk file checks. In this case, the transaction log record that is sent may be incomplete.
See also bug 49449, a related problem with transaction log records and fync timing.
Workaround
It is strongly encouraged to use the -s flag to avoid this risk; the Stone tracks the logical record boundaries and provides this information to the logsender.
Last updated: 3/17/21