> 5 min * 60 sec/min = 300 sec
> 300 sec / .02 sec/delivery = 15000 deliveries

Why on earth would you shut down delivery for the compile?

time to make install: 30 seconds
30 sec / .02 sec/delivery = 1500 deliveries

that's one order of magnitude, assuming that you need the full 30 seconds to 
do a shutdown/make install/startup.  I would believe you could get this down 
by another order of magnitude with a simple script -- making your total 
deliveries on the order of 150-250.

Speaking from experience on a mid-volume mail server (about a thousand 
deliveries per hour) -- qmail compensates perfectly.  In my case I'm also 
running every message though spamc and procmail *and* an antivirus scan (Rav 
antivirus) -- You get a 1min load spike of about 22-30 which goes away within 
a minute and you're back down to normal levels.

> What about all POP/IMAP connections ?
> Many users gets maybe less than 10 emails a day but they
> do POP their mailbox every 5 (or less) minutes !!!

You schedule it during a normal maintenance window.  Not many people are up 
and about at 4am.  And also speaking from experience, people will get an 
error, go "hmm" and try again.  By that time you're back up and nothing 

And if you really needed to look like you were always up, you'd have already 
written a very quick and dirty pop/imap server which just replied "yup, 
password good, no messages" to any query.


Reply via email to