Hello: I maintain for a large client a Postfix/MySQL installation that archives certain messages required to be held for compliance with lawsuits and employment litigation. Postfix accepts mail from the corporate mail server and delivers the message via a pipe alias to an application that is then inserting the message into the database. Recently for a large litigation matter, all mail at this company (300k messages/day) was required to be held. The server is mostly doing fine, but I have noticed that during peak delivery times Postfix will queue large amounts of mail and be slow at delivering it to the script/database -- sometimes queueing mail all the way to the weekend, when things are less busy. I've watched the time it takes from Postfix opening the application and sending the data and each message is taking ~0.003 seconds. It seems that if I could coax Postfix into sending more messages to that pipe I wouldn't have queueing issues during work days.
I've tuned the concurrency_limits from their defaults upward in steps of 5 (up to 36 now) without much luck -- I only ever seem to be able to achieve ~5 deliveries per second. I'd appreciate any guidance the gurus have to offer. FWIW, it's 2.4.3 on Mac OS X Server 10.5. Thanks, Wendy
