Mailman is Open Source... so you can feel free to open up the hood (so to speak) and take a look at how it works.
You can get Mailman to work a couple of ways, but the most common is to simply let it make an smtp call to localhost and drop off the mail similar to the way any email client would drop off a message to a mailserver. There are some differences (and I'm sure other folks will comment on them), but that is basically it. You can set Mailman to drop off each message to each person individually (often refered to as VERP) thus allowing personalization of messages, but by default Mailman will group same domain messages together - up to 100 at one time (but configurable). The Mailman/Qmail combo is very fast, as is the Mailman/Postfix combo. The local delivery is not even a bump on the road when it comes to pushing messages out into the internet. The main time constraints for email movement are in the Mail zone (DNS) look ups and the handshakes with various Mail servers around the Internet. If you run a local caching DNS on the same box as Mailman and your MTA then this helps a great deal. After that the next best improvement you can make is to use an optimized MTA (like Qmail, Postfix, or Exim). An optimized MTA re-queues slower servers to the rear of the line so that the faster ones don't have to wait. This means that 90% of your mail flies out quickly and is not held hostage in a queue behind some slow-assed server connections. Alas poor Sendmail, it doesn't downgrade the slow connections so if a few of the first servers it attempts to contact are dreadfully slow then all the mail simply waits queued up until those servers are done. So what's the point of this ramble: The speed of dropping off your mail to your local MTA is not going to effect the speed of the mailing list. It doesn't matter how fast you slam your mail's into line, they still have to wait for the MTA to push them across the internet. So the best you can do is get an optimized MTA. Best wishes - Jon Carnes On Thu, 2003-01-23 at 11:51, Jonathan Chum wrote: > I'm interested on how Mailman is able to deliver out emails rapidly. I'm > curious on whether it opens a pipe to Sendmail or Qmail, injects the > message, then closes the pipe after each message it delivers or does it > write a file directly into a queue folder waiting to be sent... > > The reason I ask is that people say SMTP is faster than mailing via Qmail > and that by opening/closing a pipe to Qmail, it adds more overhead. Also, > you'll fill up disk space faster by queuing up messages than to directly > email the message. > > I'm weighing down alternatives and method of mail delivery for a large > client of ours. > > > Regards, > Jonathan Chum > Systems Developer > > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > A I S M e d i a , I n c . > "We Build eBusinesses" > 115 Perimeter Center Terrace > Suite 540 > Atlanta, GA 30346 > Tel: 800.784.0919, Ext 502 / Fax: 770.350.9409 > http://www.aismedia.com / [EMAIL PROTECTED] > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > > ------------------------------------------------------ > Mailman-Users mailing list > [EMAIL PROTECTED] > http://mail.python.org/mailman/listinfo/mailman-users > Mailman FAQ: http://www.python.org/cgi-bin/faqw-mm.py > Searchable Archives: http://www.mail-archive.com/mailman-users%40python.org/ > > This message was sent to: [EMAIL PROTECTED] > Unsubscribe or change your options at > http://mail.python.org/mailman/options/mailman-users/jonc%40nc.rr.com ------------------------------------------------------ Mailman-Users mailing list [EMAIL PROTECTED] http://mail.python.org/mailman/listinfo/mailman-users Mailman FAQ: http://www.python.org/cgi-bin/faqw-mm.py Searchable Archives: http://www.mail-archive.com/mailman-users%40python.org/ This message was sent to: archive@jab.org Unsubscribe or change your options at http://mail.python.org/mailman/options/mailman-users/archive%40jab.org