Relation between max_servers and ncpu

[Renato Botelho]

Hello,

I run a server with postfix + amavisd-new + clamav + spamassassin, this
server have 8 cores and 16Gb of RAM. We have max_servers=6 set on
amavisd.conf and it works as expected, but, when a good number of emails
come at the same time, it takes a long time to process the entire queue.

I did a simple math average, email are taking about 3s to be processed.

I'm considering increase max_servers on this environment, but i'm worried
about if I set it to a number bigger than the number of current CPUs won't
be a problem for the other services running in this machine.

Do you have any consideration about that subject? How is the best way to
define max_servers value?

Best Regards
-- 
Renato Botelho