> My users are used to have a message delivered in a few seconds, despite of > destination.
If you really mean 'delivered' in the sentence above, then I am afraid your users have, sort of, incorrect expectations. All anyone may reasonably expect is that the mail server processes and attempts to send mail as quickly as possible. It's not like anyone can control the availability of other people's mail servers. And you have to admit that, from what you describe, your qmail toaster does process things quickly and delays are due to receiving MTAs? > But when a "ligh" mailing list, or a message with 20 or 50 recipients, > contains a nice number of recipients for the same domain, delivery of some > messages takes dozens of minutes, because destination MX delay my servers. > With the change I ask, I'd have the same quality of service for small traffic. > For large deliveries, I'm thinking to a patch for changing qmail queue > (sending to a low priority mail queue), so I will not care of large mailing > lists or messages with hundreds of recipients. If delivery of some messages takes dozens of minutes, the connection to that host itself seems slow? Reducing the number of SMTP-connections surely would save some bandwidth, but the bulk of the bandwidth should still be the message content itself, so I would expect it to still be slow. Are you sure the destination is not e.g. a tarpit or something? There might be other reasons for the delays you see... Also note that, if you send one mail to 50 recipients, this will result in 50 individual items in the queue. As long as but one of these items is still unsent, qmailctl queue will list all 50 items as still being in the queue but will indicate with each item if said item has been sent. Once all items belonging to the message have been sent, they'll all no longer be shown in the queue. Is that the behavior you see when saying some messages need a long time to send? Martin --------------------------------------------------------------------------------- Qmailtoaster is sponsored by Vickers Consulting Group (www.vickersconsulting.com) Vickers Consulting Group offers Qmailtoaster support and installations. If you need professional help with your setup, contact them today! --------------------------------------------------------------------------------- Please visit qmailtoaster.com for the latest news, updates, and packages. To unsubscribe, e-mail: qmailtoaster-list-unsubscr...@qmailtoaster.com For additional commands, e-mail: qmailtoaster-list-h...@qmailtoaster.com