On Sun, 2012-09-02 at 15:39 +0000, Viktor Dukhovni wrote: > On Sun, Sep 02, 2012 at 10:43:07AM +0100, Sam Jones wrote: > > > More to satisfy my own curiosity than anything else, I'm wondering about > > the performance that could be squeezed out of Postfix in a bulk mailing > > capacity. > > Running a high volume bulk email platform is not a software problem. > It is a logistics problem. Enrolling on the whitelists and feedback > loops of various large email providers, handling bounce-backs, > jumping through rate-limit hoops, ... > > > > I have a client that currently uses and ESP who have an astounding > > throughput of up to a million messages per hour. > > This is not astounding, a single ~2003 Dell 1850 Postfix server > was measured by me at ~300 msgs/sec of deliveries to real users > with nothing but a simple MegaRAID controller (with battery cache) > striping two SCSI disks. This would go another factor of 2 faster > on today's commodity servers, but the real issue is finding peers > who'll accept your mail at that rate. > > > discussion about high-performance MTAs and tuning and the general > > comments I'm hearing are that things like Postfix, Exim, Sendmail & > > are just not man enough for such a task and the absolute best you could > > expect from any of them is about 100k messages per hour. > > Many bulk email services in fact use Postfix, Exim, ... The MTA > software is often not the bottleneck. They split bulk deliveries > over many machines (or lots of IPs on the same machine) and tune > to avoid throttling by the ESP over and above all other concerns. > Raw MTA performance is rarely a factor. > > > Now, I like to wipe out the fact from fiction because people like > > PowerMTA are looking to sell their products and it would be in their > > interest to neglect that any MTA (Postfix/Exim/Sendmail) could be set up > > in a way that would easily rival their product. > > Bulk email is a logistics exercise. When you choose an bulk email > delivery service, you're buying their logistics skills and their > reputation with mailbox providers (Gmail, Hotmail, Yahoo, ...) > > > Can anyone on the list tell me if it's possible to performance tune > > Postfix to a point where it could complete with this and possible > > strategies? > > Wrong question. > I really appreciate the post Viktor. Thought provoking and clear.
I guess what I'm querying in a way is some of the sales blurb from people like PowerMTA & GreenArrow and the remarks they make about open source solutions like Postfix etc. This one in particular: "Open source Mail Transfer Agents (MTAs) often max out between 20 and 30 thousand messages per hour. GreenArrow can send 300,000 messages per hour—more than ten times as fast." If we strip this back to hypothetical and assume a perfect world without any issues like rate limiting and rejection, small emails with nomay restrictions or network issues with the recipient MX's, is the above statement plausibly true? I'm assuming - and I've not yet looked deeply at this - that there is probably a way to get Postfix to run parallel instances to improve delivery speed.
