Re: [Exim] Re: Very large mailing lists (Exim vs Isocor)

On Sun, 9 Apr 2000, Dave Cinege wrote:

> I should mention some specs. These guys are on dual DS1's and hitting a
> limit of 30K message output an hour. This is much to slow for them. Aside
> from revamping the MTA setup itself, the plan is to spread outbound SMTP across
> several machines and revamp the network for good load balancing.

30K messages/hour is only 8 messages/sec. Our lists (using qmail) average
that when they are going, and peak out at 13msg/sec. This is all on a P133
w/64M ram and IDE disks. Primarily we are disk bound (on the fsyncs of the
user list)

I *expect* postfix and zmail can both get similar numbers, give or take a
percent without too much trouble. Exim/sendmail I think it would be hard
to push it up to those concurrency levels.

The only reason we get those rates is due to the 240 concurrent outbound
delivery processes - that is the critical factor when you are doing lists,
you want to maximimze concurrancy so that slow remote hosts do not hold up
the works, we typically have over 50 'slow' connections that hang around
and gum things up.

Jason