We have been using Zimbra OS for quite some time now. We are quite happy with it and my deepest congratulations goes to the Zimbra team. However, we have been experiencing a serious slow down on the system as time passes, to the point of making it unusable at times.
Zimbra 5.0.14 GA is installed in a virtual machine running Ubuntu 8.04. This machine has 2.5 Gb allocated of the total 4 of the physical server (which besides that only runs a small web server)
Right now we have only 4 users, at some point in the past we were up to 8. That is what I mean by a very small installation. The only thing not small is mailbox sizes. Most of us have mailboxes that span years of emails and go up to 4 Gb of mails. We do not want to get rid of that info but I'm wondering if that may be the problem.
Anyhow, if we restart the machine the system works perfectly, however, after some hours of use it start to slow down. After several day we start getting errors from the web client saying that the server is taking too long to answer.
I have taking a look at the system and it does not seam to be a problem with memory. Swap is 0.
Most of the time doing top would give me a CPU utilization for the system around 70%, while from restart to a few hour it would run with at least 50% idle.
I thought it may be the amount of span receive and so on but we are getting around 40 messages/hour. It does not seem too many for me but I do not have that much experience.
Could anybody point me to what could be the cause of this behavior?
Any info would be greatly appreciated