Pernicious problem with vfork / qmail / qmail-scanner

[Justin Baugh, KSC]

> This error means means you`ve run out of memory (RAM + swap). Add RAM or
> swap, or lower your concurrencies or stop unneeded processes. Have you
> checked your memory? Qmail-scanner is *very* resource intensive as it is a
> huge perl program, which then calls KAV, and I have a feeling this is
> where the problem is.. are you running KAV in daemon mode? I think KAV is
> where to look.. You can also set up your server to relay mail to a
> separate server which has KAV and/or spamd and have it run over these, and
> back to the main server for delivery.

This machine has 2 gigabytes of RAM and 4 gigabytes of swap. I would 
have to run several hundred simultaneous processes to even get close to 
that limit. Even when the problem is occuring I have about 1400mb of 
inactive RAM and I have had no swap usage. In the past I ran 10, 15, 20 
deliveries concurrently on smaller footprints with no problems, albeit 
under 4.x.

Even assuming every mail delivery took up 50mb (we'll take some kind of 
ridiculous worst case, it's more like 8-12mb), I would think I'd still 
be able to have at least 20 concurrent deliveries since there are no 
ulimits, right?

-Justin