[Mailman-Users] Slow delivery

[Brad Knowles]

At 3:14 PM -0800 3/8/07, Herman Privyhum wrote:

>  Where else should I look for things that could be
>  causing this?  Exim only has problems with mail routed
>  through Mailman.

Look at your MTA logs.  They should show you when a given message 
comes in for a given user, and when that is successfully transmitted. 
I'd be willing to bet you're waiting on DNS timeouts at the remote 
end for one or more of your users -- their MTA is slowing you down, 
maybe as a result of trying to do a reverse DNS lookup on your IP 
address.

If you haven't already enabled it, try turning on full 
personalization, so that you send a unique copy of the message to 
each recipient.  For each recipient, look at the date/time stamp of 
when the message goes into Exim and when Exim says that the remote 
end has accepted the message.  That should tell you where things are 
slowing down.

Maybe it's not a DNS timeout, maybe it's a timeout of some other 
sort.  Maybe it's a result of doing anti-spam/anti-virus processing 
on inbound as well as outbound e-mail.  Maybe their mail servers are 
just very slow.  But at least you should know where the slowdown is 
coming from.


You may also be able to turn on some increased parallelism in the 
delivery process, so that other recipients can be handled while 
you're waiting on the slower sites to respond.

But I wouldn't feel bad at getting everything out in 30 seconds.

-- 
Brad Knowles <brad at shub-internet.org>, Consultant & Author
LinkedIn Profile: <http://tinyurl.com/y8kpxu>
Slides from Invited Talks: <http://tinyurl.com/tj6q4>