Ok, I am also seeing that problem, below is an excerpt from the faq. I am using sendmail for my MTA, how would I turn this off on my box? I looked in README.SENDMAIL and it didn't address it.
Eric
Q. I'm getting really terrible performance for outgoing messages. It seems that if the MTA has trouble resolving DNS for any recipients, qrunner just gets really slow clearing the queue. Any ideas?
A. What's likely happening is that your MTA is doing DNS resolution on recipients for messages delivered locally (i.e. from Mailman to your MTA via SMTPDirect.py). This is a Bad Thing. You need to turn off synchronous DNS resolution for messages originating from the local host.
In Exim, the value to edit is receiver_verify_hosts. See README.EXIM for details. Other MTAs have (of course) different parameters and defaults that control this. First check the README file for your MTA and then consult your MTA's own documentation.
> -----Original Message-----
> From: Danny Terweij [mailto:[EMAIL PROTECTED]]
> Sent: Friday, April 26, 2002 6:49 AM
> To: [EMAIL PROTECTED]; [EMAIL PROTECTED]
> Subject: Re: [Mailman-Users] Long delay for qrunner ?
>
>
> From: "Jon Carnes" <[EMAIL PROTECTED]>
> > Are messages going out from Mailman? In otherwords, is
> qrunner stuck on
> one
> > or two messages?
>
> Every message is going out. But qrunner is very slow (or
> something else).
>
> With ps ax i see :
>
> 4609 ? R 41:19 /usr/bin/python -S
> /var/mailman/cron/qrunner
>
> Danny.
>
>
>
>
>
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