DB IDO: When to clean up inactive objects

The Icinga 2 network monitoring daemon (version: 2.12.1-1)

icinga_objects table has the is_active column ,that indicates whether the service/host is deleted from the configuration.
I found that some objects will be deleted from the database a few days after being deleted from the configuration, and some objects will still exist in the database a few months after being deleted from the configuration.
Does icinga clean up these inactive objects according to predetermined rules? Can this rule be modified through configuration?
I will be very appreciated if you could give me an early reply.

object IdoMysqlConnection "ido-mysql" {
  user = "icingaha"
  password = "icinga09"
  host = "mysql-cn"
  port = "3306"
  database = "icingha"
  cleanup = {
    notifications_age = 180d
    contactnotifications_age = 180d