On Sun, Aug 19, 2001 at 11:53:25PM -0700, PHP Webmaster allegedly wrote:
> Hello everyone,
>
> The company I am in is thinking about moving their
> opt-in email newsletters from a third-party service
> bureau to in-house.
>
> I was wondering what would be the minimum hardware
> configuration and qmail setup needed to be able to
> send 6 million emails within 24 hours as this is a
> daily newsletter?
>
> On tests done on a dual p3-800 with 1 gigabyte of ram
> running qmail configured according to Life With Qmail,
> I am able to send about 1080 emails per minute, or
> maximum 1.5 million emails per day.
That's pretty consistent with what others see for a single system, no
doubt using a single disk.
You haven't mentioned whether this is a single email with multiple
recipients or a customized email per recipient. That makes a big
difference to the answer.
As others have pointed out, you need to make sure you have:
o plenty of bandwidth - have you calculated what sort of bit rate
you'll need to deliver 6million * XKbyte emails per day? A 10K email
constitutes a bit rate of close to 6MB/s. At that rate you'll want
at least 12MB/s of bandwidth.
o Plenty of disk spindle - I would spread the delivery across multiple
machines, each with their very own fast /var/qmail. How much
recovery time do you have if the machine goes down?
o Good dns caching - you're going to be doing a lot of DNS lookups, is
your current cache setup up to it? Are you running your own cache?
You'll want to.
> perform at 1080 emails per minute when the
> concurrencyremote was set at 100, increasing to 118
> had apparently no effect on the number of emails sent
> per minute.
Which is your system telling you there is some other bottleneck. What
performance measurements did you make during this test? What did you
discover about your disk, CP, bandwidth, memory and DNS?
> Can anyone kindly provide me with insight on how to
> best configure qmail to handle 6 million emails per
> day? Is this possible on a single server setup and if
> so how?
Assuming you mean a single server in the sense that most do now, an
Intel box with a disk or two, then I'd be very surprised if a single
server could do it. If you mean a fire-breathiong monster the size of
a fridge with a dozen high speed disks and a $100K price tag, then
sure.
Remember that you need to have plenty of spare capacity to recover
from the inevitible down times. A system that delivers in 23 hours is
way too vulnerable to some sort of downtime pushing your delivery
schedule out past your deadline. A good rule of thumb is to use no
more than 50% of your resources on a normal day - that includes time!
Also remember that you will get a substantial number of bounces with
this sized list. You'll need plenty of horse-power to manage the
bounces and probe management. You will be using VERP style envelope
addresses to track bounces of course.
Regards.
