Run an aggressive VACUUM FREEZE
PostgreSQLMaintenanceCommand
VACUUM (FREEZE, VERBOSE, ANALYZE) customer;What it does
Immediately marks all eligible tuples in the table as 'frozen'; reduces transaction ID wraparound risk.
When to use it
When a wraparound warning appears, or preventively on large tables that will be archived/become read-only.
Caution
Generates heavy I/O because it scans the entire table. In a wraparound emergency the database can effectively go read-only; monitor datfrozenxid beforehand.