The mailbox server has four 2.2Ghz Xeon cores and 8GB RAM. MTA/Spam services are on another box, and it's the mailbox server that gets overloaded. I've tried this both with sympa configured to allow as many as 2000 recipients per message or as few as 50. The latter works much better, but still places a noticeable lag on the server.
I think we're doing about 300K messages per day normally, and as part of our transition, we still have a separate postfix/spamassassin MTA in front of the pair of zimbra filters for external traffic, so the zimbra MTA shouldn't be working that hard on spam.
I could probably make do with the Zimbra distribution lists if the internal lists were all we had, but I think people are still going to want archives of those lists, and we will still have a handful of public lists that zimbra can't really handle. So it seems silly to hack a pseudo LDAP setup into zimbra when sympa gives it to us so easily. |