System Performance Snapshot

enable_wdr_snapshot

Parameter description: Specifies whether to enable the database monitoring snapshot function.

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

Value range: Boolean

• on indicates that the database monitoring snapshot function is enabled.
• off indicates that the database monitoring snapshot function is disabled.

Default value: off

wdr_snapshot_retention_days

Parameter description: Specifies the number of days database monitoring snapshots are retained. When the value of wdr_snapshot_retention_days is exceeded, the system cleans up snapshots with the smallest snapshot_id at the interval specified by wdr_snapshot_interval.

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

Value range: an integer ranging from 1 to 8

Default value: 8

wdr_snapshot_query_timeout

Parameter description: Specifies the execution timeout for the SQL statements associated with database monitoring snapshot operations. If the SQL statement execution is not complete and a result is not returned within the specified time, the snapshot operation fails.

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

Value range: an integer ranging from 100 to INT_MAX. The unit is s.

Default value: 100s

wdr_snapshot_interval

Parameter description: Specifies the interval at which the background thread Snapshot automatically performs snapshot operations on the database monitoring data.

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

Value range: an integer ranging from 10 to 60. The unit is m.

Default value: 1h