[Mailman-Users] High usage -- making Mailman "nice"

[Caylan Van Larson]

On Dec 8, 2005, at 12:49 PM, Brad Knowles wrote:

> At 1:12 PM -0500 2005-12-08, John Dennis wrote:
>
>>>  We're running MM v2.1.4-4, we're experiencing such high usage on  
>>> our
>>>  dual xeon server when mailman sends to 4000 users that port 25
>>>  becomes unresponsive.  is there a way to "nice" the mailman  
>>> delivery?
>>
>>  It sounds like your MTA is inefficient in some manner, is not a huge
>>  load for a dual server backed with a high bandwith connection.  
>> How many
>>  client connections can it simultaneously handle? Any chance  
>> you've got
>>  DNS delays (especially reverse lookup)?
>
> 	They could also be doing all sorts of authentication/authorization  
> or anti-spam/anti-virus checks on their outgoing mail.
>
> 	It is clearly stated in the FAQ that this is generally a bad idea  
> for outgoing mail from the mailing list, since all that stuff  
> should have been checked on the way in.

Thanks for all those that responded.  After thinking about this for a  
bit, we realized that we were using a content-filter in postfix to  
divert all incoming port 25 to a barracuda spam appliance.  This was  
then coming back in 10027 for delivery.

To further amplify the problem, /home is NFS mounted... which means,  
lots of network IO.

Here are the changes we made.

mm_cfg.py
	SMTP_MAX_RCPT = 2000
	SMTPPORT=10027

main.cf
	smtpd_recipient_limit = 1000
	default_process_limit = 150

Thanks,

Caylan