Re: [Exim] Performance issues

> I am running exim 3.36 on a single P4 1.6GHz RedHat 7.3 machine with 768mb =
> of RAM. A single Perl programme is generating email. It seems that we have =
> a capacity limit on that machine of 12,250 deliveries per hour.

You did not say if the machine runs CPU or disk bound, so I guess
neither applies. You may have a problem with latencies, e.g. DNS lookups
(no local DNS cache), ident lookups (disable those) or hints access
(put the hints databases on a tmpfs).

It may help to strace(1) the daemon with timestamps to see where
exim pauses. I inject messages to a MX of mine over SMTP with 100
recipients per message at the rate of 3-5 minutes per 100 messages (yes,
that are 10.000 adresses in a few minutes). The machine explodes them
and delivers them without queing during that interval - besides handling
its regular traffic.

Michael