Results 1 to 2 of 2

Thread: The real meaning of queue_run_delay?

  1. #1
    Join Date
    Aug 2008
    Rep Power

    Default The real meaning of queue_run_delay?

    Who can give an detial explainantion of queue_run_delay . I read the document "Reconfiguring Postfix Deferred Queue Parameters" ,but still not understand the sure meaning of it. I will appreciate if you can give some examples ? Thanks !
    Ask Forever...

  2. #2
    Join Date
    May 2006
    Rep Power


    The queue manager scans the deferred queue periodically; the scan interval is controlled by the queue_run_delay parameter. While a deferred queue scan is in progress, if an incoming queue scan is also in progress (ideally these are brief since the incoming queue should be short), the queue manager alternates between looking for messages in the incoming queue and in the deferred queue. This technique prevents starvation of either the incoming or the deferred queues.

    Each deferred queue scan only brings a fraction of the deferred queue back into the active queue for a retry. This is because each message in the deferred queue is assigned a "cool-off" time when it is deferred. This is done by time-warping the modification time of the queue file into the future. The queue file is not eligible for a retry if its modification time is not yet reached.

    The "cool-off" time is at least minimal_backoff_time and at most maximal_backoff_time. The next retry time is set by doubling the message's age in the queue, and adjusting up or down to lie within the limits. This means that young messages are initially retried more often than old messages.

    (default: 300s) The time between deferred queue scans by the queue manager. This parameter should be set less than or equal to minimal_backoff_time.

    minimal_backoff_time (default: 300s) The minimal time between attempts to deliver a deferred message. When a message is first placed in the deferred queue, the value of this setting is what determines when the first attempt to redeliver the message is made. This parameter also limits the time an unreachable destination is kept in the short-term, in-memory, destination status cache. This parameter should be set greater than or equal to queue_run_delay.

    maximal_backoff_time (default: 4000s) The maximal time between attempts to deliver a deferred message. The time between each attempt to deliver a deferred message will grow exponentially until it reaches the value in this setting. The attempted deliveries are repeated at this value until the queue lifetime is reached. This parameter should be set to a value greater than or equal to minimal_backoff_time.

    bounce_queue_lifetime & maximal_queue_lifetime (default: 5d) The max time a bounce message & max time any message is queued before it is sent back as undeliverable. Specify 0 when mail delivery should be tried only once.

    Time units: s (seconds), m (minutes), h (hours), d (days), w (weeks).

    More config options listed here: Postfix manual - qmgr(8)

Similar Threads

  1. Zimbra Cluster Installation
    By veronica in forum Installation
    Replies: 1
    Last Post: 06-25-2008, 01:55 AM
  2. Real World Server Requirements
    By DEREKB in forum Administrators
    Replies: 15
    Last Post: 04-07-2008, 01:33 AM
  3. Replies: 0
    Last Post: 05-18-2007, 01:33 AM
  4. REAL Debian port
    By rexxmo in forum Installation
    Replies: 4
    Last Post: 11-14-2006, 07:55 AM
  5. Real AJAX example and resizable tree
    By Heladito in forum Developers
    Replies: 3
    Last Post: 10-28-2005, 09:43 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts