[exim] Fastest Exim server ever

I just got a call from someone wanting to be able to send 50k email
messages a second. Most of it in bursts of a few seconds long. It has to
do with some kind of gaming application. I'm just trying to picture in
my mind what kind of hardware could do that.

What the Exim record for how fast a server can send email? Anyone have
some numbers?

As to being fast, I'm thinking that lots of ram would be necessary. The
you put the queues in ram disk and you have a fall back server so it
tries to deliver one time and if it fails to laterals the message off to
another server that queues the messages for normal retry delivery. And
I'm thinking you would have a separate DNS server dedicated to caching
lookups.

Thoughts?