PostgreSQL version:


Sets the minimum amount of table data that must be scanned in order for a parallel scan to be considered. For a parallel sequential scan, the amount of table data scanned is always equal to the size of the table, but when indexes are used the amount of table data scanned will normally be less. The default is 8 megabytes (8MB).


… , unless doing IoT or a read-only database. Raise to 100MB or so if your traffic on the database is very bursty, to prevent the WAL from shrinking too much.