Matthew Hodgson wrote:
> Hi all,
>
> I have the problem of a very large mail queue which contain lots of
> messages sent to the same remote address. Unfortunately the MX servers
> for the remote domain are rather slow, and so when performing a queue
> run in exim 4.66 the messages are trickling through very slowly as each
> connection takes about 30 seconds to establish.
>
> How can I persuade exim to send multiple envelopes to the same MX server
> in the same SMTP connection to avoid the connection overhead? I've
> found the queue_smtp_domains option, which appears to only be useful for
> messages which are yet to be queued (and kills the possibility of
> instant deliveries if there's no need to queue). How do I get normal
> queued messages to add entries to the wait-remote_smtp hint database, so
> that when delivering a message to the remote server it will hand the TCP
> connection over to deliveries for other pending messages?
>
> Enlightenment would be hugely appreciated :)
Check out "30.1. Multiple messages on a single connection"
http://www.exim.org/exim-html-current/doc/html/spec_html/ch30.html#SECID144
It seems to say that multiple messages to the same host (as per recorded
in the retry database) are handled on the same connection as much as
possible.
If they are different domains at the same host, look into "multi_domain"
in the same section.
I remember something about "same domain copy routing" but I can't find
it anywhere in the documentation.
If you can't seem to shake the delays, you may want to talk to the
postmaster at the domain as they probably have to tar-pitted or
something similar.
