Rajkumar S wrote:
Hi,
Does any one seeing increasing smtp concurrency for the past couple of
weeks? I run couple of (qmail/simscan/spamassassin) mail servers and
all experience the same problem. The spam does not increase, but this
is hogging my mail servers. Probably a new crop of spamming tools?
I am attaching one qmail-mtrg graph that shows the problem.
http://img403.imageshack.us/img403/2224/smtpmonthyq4.png
Yeah, two weekends ago our mail servers got absolutely slammed with
connections that were left open. They'd get rejected, and then leave the
connection open for a while, then try again, and so on.
Our count of exim processes per server went up from our already
higher-than-it-recently-used-to-be 500 to around 1,000. This continued
on monday, climbing to around 1300. Restarting exim and killing off
these old connections would only relieve it for ten minutes or less.
When it hit 1500, we moved a few of our rbls to the connect phase, which
brought it down to about 150 exim procs. Yeesh...
--
Gus
