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 |=--