Timothy L Mayo <[EMAIL PROTECTED]> writes:
> Neither Keith nor I are talking about the mailer. If the remote MACHINE
> cannot handle the load, it should be set up to reject the excess
> connections. This is true no matter WHAT MTA is running on the remote
> system.
This is great in theory. In practice, does your tcpserver setup
automatically start refusing connections when you're low on queue space or
when you know the load will be too high? I bet it doesn't.
The reason why it doesn't isn't because it's poorly designed. It's
because it's hard to do this. You have to be partially psychic in order
to always catch it.
sendmail has a bunch of load-limiting features, particularly in the latest
versions. It can start queuing instead of mailing directly, it can refuse
connections entirely, and it can do this on the basis of the current
number of running daemons, system load, or disk space. It's still
relatively easy to make a machine running sendmail fall over under load.
It's harder for qmail primarily because qmail is small and fast, not
because it has any better load management capabilities near the boundary
of what the machine can cope with than sendmail does.
--
Russ Allbery ([EMAIL PROTECTED]) <URL:http://www.eyrie.org/~eagle/>
