PUBLIC MARKS from camel with tags zimbra & xen

Out of the box, Zimbra is tuned for a fairly beefy machine. Zimbra will easily consume 1.5GB of ram with default settings. Some of these changes mean turning off a few Zimbra features and there are quite a few ways to do this, so you will need to evaluate memory usage given your own situation. If you simply can't live without *all* the Zimbra features or intend to support a larger (> 15) number of users, my only suggestion is to get more ram ;). But if you are willing to make some compromises, please read on. The changes below are ones that I found to be a reasonable compromise. With a few easy changes, you can bring the memory consumption way down, so that it will hum along just fine on a server with ~512MB of ram. Of course this reduces the amount of users that your server can support, but I've found that for a small installation of around 15 users, these settings will work just fine and give you the same performance as the out-of-the-box config with gobs of RAM. The server I have been testing with has 560MB of ram, and after tuning consumes all the ram and only about 80MB of swap on average. You will find that if you don't make changes similar to the ones suggested below with ~512MB of ram, your Zimbra install will slowly creep up its consumption of swap and your Zimbra install will start to crawl. Also, > 512MB seems to be about the minimum amount of ram to get a useful/zippy server