Archiving

archive_timeout

Parameter description: Specifies the archiving period.

This is a SIGHUP parameter. Set it based on instructions in Table 1.

• The server is forced to switch to a new WAL segment file when the period specified by this parameter has elapsed since the last file switch.
• Archived files that are closed early due to a forced switch are still of the same length as full files. Therefore, a very short archive_timeout will bloat the archive storage. You are advised to set archive_timeout to 60s.

Value range: an integer ranging from 0 to 1073741823. The unit is s. 0 indicates that archiving timeout is disabled.

Default value: 0

archive_interval

Parameter description: Specifies the archiving interval.

This is a SIGHUP parameter. Set it based on instructions in Table 1.

• Log files are forcibly archived when the period specified by this parameter has elapsed.
• Archiving involves I/O operations. Therefore, frequent archiving is not allowed. In addition, the RPO cannot be set to a large value; otherwise, the PITR will be affected. You are advised to use the default value.

Value range: an integer ranging from 1 to 1000. The unit is s.

Default value: 1

time_to_target_rpo

Parameter description:

In the remote DR mode of dual database instances, set the allowed time_to_target_rpo seconds from the time when an exception occurs on the primary database instance to the time when data is archived to the OBS recovery point.

This is a SIGHUP parameter. Set it based on instructions in Table 1.

Value range: an integer ranging from 0 to 3600. The unit is s.

In remote DR mode of dual database instances, logs of the primary database instance are archived to OBS. 0 indicates that log flow control is disabled. 1 to 3600 indicates the maximum time_to_target_rpo seconds from the time when an exception occurs on the primary database instance to the time when data is archived to the recovery point of OBS. This ensures that the maximum duration of data loss is within the allowed range when the primary database instance breaks down due to a disaster. If this parameter is set to a small value, the performance of the primary node is affected. If it is set to a large value, the log flow is not effectively controlled.

Default value: 0