>With some custom code tweaks (not yet released to the public, but look
>out for them) and adequate RAM and network speed, I've actually stayed
>stable  with  MaxQueProcs  as  high  as 200. Don't try that on a plain
>system, though.

I've built custom FreeBSD kernels with maxusers 128 which gives 2048 max 
processes.

In that machine, I've set max SMTP processes to 400, and max SMTPD 
processes to 400.

The multi-month DoS attack the Imail user was trying do defend against with 
IMgate consumed all 400 SMTPD processes, pegged out.  valid incoming 
mail  to the IMGate MX box could not obtain a free SMTPD process and was 
typically delayed 5 or 6 hours.

It's very frightening to see that level of incoming DoS mail from 1000's of 
open-relays around the world.  Although IMGate was rejecting all it as 
being in RBL servers, IMGate ran out of 400 processes doing the rejecting.

Len


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http://IMGate.MEIway.com  : Build free, hi-perf, anti-abuse mail gateways


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