The main issue is system resources as stated. SpamAssassin is a real pig when it comes to resources, but it works well.. We have 12 Dell Poweredge 2650's (Dual 3.0ghz each with 4 gigs of ram and 5 x 15k rpm scsi disks in a raid 1+0(/10) setup) SA is eating it alive..
Just out of pure curiosity, how do you load balance these machines? Round-robin DNS?
Layer4 switching..
Cami
