delayed_queue_scan_interval — how often to call the maintainer for a domain
delayed_queue_scan_interval = 15
The primary function of the
delayed_queue_scan_interval option is to determine how often to call the maintainer for a domain. If there are messages on the active queue, then it is called at least every delayed_queue_scan_interval. If all the messages are on the delayed queue, then the maintainer is scheduled for the next attempt on the first delayed message.
Additionally, when the maintainer is called, it will sweep any delayed messages that are ready to go onto the active queue. If there are constantly active messages,
delayed_queue_scan_interval will control how often the delayed messages get swept onto the active queue.
This option has no effect when the entire queue is delayed.
The default value is
delayed_queue_scan_interval is valid in the global scope.