I made the HUGE mistake of putting the clerk@tm9-801.com email address on a page that used a google service. PROTIP: Don't ever put an email address on a page that uses anything google.. it will be harvested and become a useless spam pot.
But here are some interesting stats.. I get about 100-150 spams a day to that email address. Here is a snippet of the spamassassin log file:
Oct 18 15:06:02 spamd[15194]: spamd: identified spam (6.2/2.7) for spamd:502 in 3.8 seconds, 12630 bytes.
Oct 18 15:13:49 spamd[15194]: spamd: identified spam (12.5/2.7) for spamd:502 in 4.3 seconds, 9518 bytes.
Oct 18 15:16:14 spamd[15194]: spamd: identified spam (7.0/2.7) for spamd:502 in 1.0 seconds, 17994 bytes.
Oct 18 15:20:59 spamd[15194]: spamd: identified spam (12.7/2.7) for spamd:502 in 0.4 seconds, 10215 bytes.
Oct 18 15:45:52 spamd[15194]: spamd: identified spam (9.1/2.7) for spamd:502 in 5.2 seconds, 11760 bytes.
Oct 18 15:51:55 spamd[15194]: spamd: identified spam (7.4/2.7) for spamd:502 in 3.7 seconds, 30514 bytes.
Oct 18 16:06:15 spamd[15194]: spamd: identified spam (12.0/2.7) for spamd:502 in 4.8 seconds, 9806 bytes.
Oct 18 16:45:29 spamd[15194]: spamd: identified spam (3.3/2.7) for spamd:502 in 4.8 seconds, 13880 bytes.
Oct 18 17:04:46 spamd[15194]: spamd: identified spam (11.4/2.7) for spamd:502 in 41.0 seconds, 6037 bytes.
Oct 18 17:06:18 spamd[15194]: spamd: identified spam (6.2/2.7) for spamd:502 in 4.6 seconds, 11973 bytes.
Oct 18 17:08:10 spamd[15194]: spamd: identified spam (4.1/2.7) for spamd:502 in 1.2 seconds, 25423 bytes.
Oct 18 17:09:20 spamd[15194]: spamd: clean message (0.3/2.7) for spamd:502 in 0.4 seconds, 5507 bytes.
Oct 18 17:10:22 spamd[15194]: spamd: clean message (0.1/2.7) for spamd:502 in 0.3 seconds, 3982 bytes.
Oct 18 17:13:35 spamd[15194]: spamd: clean message (0.7/2.7) for spamd:502 in 0.5 seconds, 13113 bytes.
Oct 18 17:14:34 spamd[15194]: spamd: clean message (-2.0/2.7) for spamd:502 in 0.8 seconds, 44815 bytes.
I run 3 spamd processes that consume about 35% of the servers memory (its a virutal server, 256Mb max ram) and looking at the logs the average time to run an email through the filters is about 2-3 seconds. I get about 1 email *roughly* every 10 minutes. Each spam is about 20Kb.
Looks like I can turn off at least one, possibly two spamd processes and still not affect mail delivery. Also by grepping the log file for the PiD of the spamd process I can even tell when I actually use a second or third spamd process.. the PiD will change.
While its not going to make a huge difference... more RAM for sql or apache services is always better used than simply letting a spamd process sit there.