[Mailman-Users] Large Lists manipulations

[J C Lawrence]

On Wed, 5 Dec 2001 08:28:53 -0500 (EST) 
tass  <tass at kenderhome.com> wrote:

> SCSI alas is not an option (which is where I think the bottleneck
> is).  It is an 80GB IBM EIDE hardrive with UDMA66 Celeron 500
> 686class 512M Ram

Its a little difficult to say much without knowing how much list
traffic you'd be dealing with or what your outbound bandwidth is.
Assuming reasonable outbound bandwidth (T1+), a posting rate of
~10 messages a day, and ~10% slow MX'es, I'd:

  -- set SMTP_MAX_RCPTS to be reasonably large (in the 50 - 100
  range)

  -- make sure I had a local cacheing nameserver installed
  (recommend: pdnsd)

  -- tune my MTA to be sensitive to system load.  Using Exim as the
  MTA would make this particularly easy.

  -- tune the MTA for rapid fall-offs for slow MX'es and hard
  bounces no later than 4 days (as per RFC recommendation).

Note that running a 10K member list on such hardware is not
inherently a problem.  It can and should work quite nice without
much stress or strain.  It all really depends on two  things:

  1) How busy the list is

  2) What your percentage of slow MX'es is (which controls what your
  average queue size is).

The less saturated the system is, the more attractive Postfix is as
an MTA.  Nicely enough, Postfix is fast enough and clever enough in
its spool handling that it will delay the saturation point
significantly.  However, if you are at or near saturation point the
Exim's queue handling will be a lot nicer to you and your system,
with its graceful fall-offs for system load.

> I have about 80% disk cap still open

If you can, throw another disk in there, then put /var/spool/<MTA>
on it and put it on a __different___ IO chain from your main drive.
This will reduce IO and head contention for your mail spool.

-- 
J C Lawrence                
---------(*)                Satan, oscillate my metallic sonatas. 
claw at kanga.nu               He lived as a devil, eh?		  
http://www.kanga.nu/~claw/  Evil is a name of a foeman, as I live.