2009/7/30 Christian Wittwer <wittwe...@gmail.com>: > I'm trying to setup a postfix enviroment to relay about 200k mails per hour. > The hardware and the network link will be well dimensioned, so I like > to talk about the configuration part of this setup. > There are several options to tune in postfix, like timouts and > concurrent sessions etc.. > > My idea was basically to setup two smtp services. > One which has very short timeouts and uses lots of concurrent sessions etc.. > A second one which takes the non deliverable mails from the first one > and tries with longer timeouts and less sessions to deliver mail. > So the first one is not blocked and can just continue to deliver, and > the second one makes the dirty work. > Does such a setup make sense to you?
I have two immediate thoughts here; short one first: How do you propose to move non-deliverable mail from the first instance to the second one? Actually, I have another small thought: I know large mailouts have problems delivering some messages, that's a fact of life. That said, can you "clean" your mailing list further? We have some customers that do large mailouts to their subscriber list and they point-blank refuse to remove bad addresses because they'd have to admit to themselves that they don't have as many subscribers as they claim to - I'm talking about hotmial.com and yahoo.coma.u, etc The real point here: To be honest, I reckon postfix is probably smarter than you. While it's easy enough to come up with cases where you could micro-manage postfix for optimal behaviour, it's had plenty of time to mature and deal with plenty of corner-cases. Postfix is nominally I/O-bound, it doesn't hang around when there's work to be done. Perhaps if you could push the hard-to-deliver stuff off to another host, that'd relieve I/O contention on the "easy deliveries", but this could well be premature optimisation. Postfix's scheduler attempts to be fair and make sure mail is delivered evenly, so one destination doesn't swamp others. There was a question about this recently, which referred to an older thread on the topic. Relevant reading: http://www.postfix.org/SCHEDULER_README.html The recent thread: http://www.phwinfo.com/forum/mailing-postfix-users/373193-re-message-priority.html Which refers to this one from a few years ago: http://www.irbs.net/internet/postfix/0407/2008.html You mentioned your hardware is already spec'ed out? I'm mildly curious what that looks like, as I published some very informal benchmark figures a while ago, showing a modest system doing ~270,000 per hour in contrived lab conditions with little optimisation.
