On Wed, 24 May 2000 09:51:29 +0100 Nigel Metheringham <Nigel.Metheringham@VData.co.uk> wrote:

Remember that unless the sender side is using qmail or VERP then 2 million addresses all in this domain would normally optomise down to a single SMTP message transaction with 2 million RCPT TO's.

Actually on the input side it would be 2M/SMTP_MAX_RCPTS where SMTP_MAX_RCPTS defaults to 500. Additionally, Exim (I haven't checked Postfix, but I doubt it) does not collapse identical spool entries with different RCPT TO lists, so you're still left with the same number (checking for identicallity is expensive).

You may also find that you get an unexpected speed up at the inject end since the domain name may (certainly should) be cached in the MTA and/or local dns server/cache and so if the MTA does verification/routing during SMTP receipt the first address would prime the config and all the others would shoot through very quickly.

True. However for anybody running such a large mailing list, I would expect them to have configured their MTA to not attempt pre-lookups for messages arriving from MailMan. Certainly that's how I've configured mine.

-- J C Lawrence Home: claw@kanga.nu ----------(*) Other: coder@kanga.nu --=| A man is as sane as he is dangerous to his environment |=--