A long time ago I wrote about using greylisting on my servers. Now, more then a year later, I accidently looked at the stats.

web:~# greylist stats
Statistics since Thu Dec 24 12:59:53 2009 (510 days and 7 hours ago)
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243 items, matching 9708 requests, are currently whitelisted
0 items, matching    0 requests, are currently blacklisted
8 items, matching   26 requests, are currently greylisted

Of 120014 items that were initially greylisted:
-   5225 (  4.4%) became whitelisted
- 114789 ( 95.6%) expired from the greylist

As you compare these results to the results from the earlier mentioned post, there is not much different in the percentage. A bit less in percentage expired from the greylisting, however, not that much.

Badly enough, if I look at the amount of spam I get in my mailbox, the greylisting is less performing as back then. Right now, I get around 100 spam emails in my inbox/spambox, instead of 10 a year back. So it looks like I need to look into some changes, as I dont like spamfiltering, as it requires CPU.