[Mailman-Developers] mailman and the web

[J C Lawrence]

On Sun, 18 Mar 2001 22:35:50 -0500 
Jay R Ashworth <jra@baylink.com> wrote:

> On Sun, Mar 18, 2001 at 10:17:04PM -0500, Barry A. Warsaw wrote:
>> In Mailman, this message would be handed off to the local MTA as
>> one copy, with 1000 recipients.  Then it would be up to the MTA
>> to do as efficient delivery as is possible.  Mailman has some
>> optional chunking parameters so that it can be tuned to your MTA,
>> but in general, it tries to hand off the message with the fewest
>> dialog with the MTA as possible, and then it gets out of the way.

> And for good reason.  From an adventure last week, on a P200:

> Time to add 1000 recipients to a list with welcome mails: 70-80
> minutes.

> Time to add 1000 recipients to a list *without* welcome mails:
> roughly 2 minutes.

Translation your MTA is misconfigured to do some sort of extra
processing (likely domain verification) on list server messages as
they are delivered.  Bad Idea (and a FAQ).

A local test:

  On a dual PII-33 with 512M RAM running Postfix under Debian/Woody
  (kanga.nu), I created a test list and then subscribed 1,000
  addresses to it via `~/bin/add_members -n members -w y`.  Total
  execution time for the add_members command: 38 seconds.

The member list in question was artificial (a set of trash
+-addresses on localhost I have set to deliver to /dev/null but
which are unique as far as postfix and Mailman are concerned).

Qrunner on the same machine, when delivering a single message to one
of my lists which has almost exactly 1,000 members (slightly over)
takes just over 3.5 seconds with SMTP_MAX_RCPTS set to 5.  I presume
the extra time for add_members is due to poor lock management, but
have not checked.

-- 
J C Lawrence                                       claw@kanga.nu
---------(*)                          http://www.kanga.nu/~claw/
--=| A man is as sane as he is dangerous to his environment |=--