I have started to test Zimbra and we love it, but I have some concerns from a system administrators standpoint. The system that we are currently running it on is a Dual 3Ghz and we are seing a 27% useage almost constant from zimbra user processes and java running zimbra. We are running RHEL 4. With this type of useage at idle what kind of load handeling capability can we expect.
if you are concerned with not being able to handle possible load, search these forums for 'clustering', and 'load balancing'. from other threads on these forums i have seen people getting 10k/day [messages] using zimbra.
you have to remember too that the java process is for the web client, so postfix should be able to handle the load of email quite easily, but the web client (via java) may lag behind a bit. of course more load on the processor also means that other process will run slower, so you might want to consider running the mail server on a seperate server to the actual web client.
That load seems very high, we've made some changes to our moniter so in the future builds any load from that should be gone. In either case we are running the same milestone 1 build on our hosted demo and don't see this.
How much memory does that server have?
It has 1GB installed in it. And at a full idle it uses that much processor.
I just looked and it went down for one snmp reading during the last 24 hours to 180% of processor.
oops, that performance value is actually 10k/30mins. :D