I use postfix without greylisting, instead I drop the message if it is going to a non-existent user (drops about 99% of all mail), then drop it if it comes from an invalid domain (there goes another 0.5%) and then a block list (cbl.abuseat.org). The rest is valid email, which gets spam/virus scanned and delivered to my mailbox. Not very CPU intensive at all...
Then it goes through amavisd that does the spamassasin checks, as well as verify DKIM and the like, and then it gets delivered to dovecot.
Now, Dovecot as an IMAP server is fantastic. Along with dovecot-pigeonhole I can sort messages into different folders server side.
Dovecot currently handles one mailbox for me that I archive a mailing list into ... 150k messages and counting, and no issues. Uses Maildir on the backend. Although, I do think at those sizes it comes down to good file system caches, and a good file system that doesn't have a problem caching the entire directory.
It works well for me, so well in fact that I am moving all my stuff from Google Apps for Domains back to in-house. For two reasons, 1. more control, and 2. I have had issues with Google Apps in the past, and even with a paid account the support has been lackluster. I'd like to know more about my email, be able to check logs if need be to see what is going on.
Then it goes through amavisd that does the spamassasin checks, as well as verify DKIM and the like, and then it gets delivered to dovecot.
Now, Dovecot as an IMAP server is fantastic. Along with dovecot-pigeonhole I can sort messages into different folders server side.
Dovecot currently handles one mailbox for me that I archive a mailing list into ... 150k messages and counting, and no issues. Uses Maildir on the backend. Although, I do think at those sizes it comes down to good file system caches, and a good file system that doesn't have a problem caching the entire directory.
It works well for me, so well in fact that I am moving all my stuff from Google Apps for Domains back to in-house. For two reasons, 1. more control, and 2. I have had issues with Google Apps in the past, and even with a paid account the support has been lackluster. I'd like to know more about my email, be able to check logs if need be to see what is going on.