I've been experimenting with 2.0b2 running under linux on my test box which is a modest celeron 2.8GHz with 2GB of RAM. I configured up a Windows XP and Slackware 12.1 VM which both appeared to run really well.
I was then experimenting with a Windows 2003 VM and decided to first make up a slipstreamed version of 2003 with SP2. I used my Windows XP VM to do this. I pushed my ISO up to the host and created a new VM to install 2003.
something went wrong in the ISO creation (wrong settings for my ISO9660 filenames) and as a result the windows installer stopped because it was missing a file. It was at this stage that I noticed that my Windows XP and Slackware VM's had idled down and all the CPU power was being used for the Windows 2003 install. The Windows XM VM became almost totally unresponsive and after around 4-5 minutes, the Windows XP VM just "shut down" all by itself.
I started to notice a trend with this - whenever I go to install a guest operating system, this new VM sucks all available CPU power and regularly causes the other Windows VM's (sitting idle) to shutdown.
All this time my Slackware VM continued to function.
My last test was a dummy install of Windows 98 SE (for no real reason ) and I got about half way through the installation and stopped to check everything out. Again, all my CPU power has gone to this new installing VM and the other sessions are almost dead. The load on my box is over 12. I've left it like this all day while I was at work.
Once the VM's have completed installation and are up and running, things appear to be ok.
My main concern here, however, is that an individual VM can dominate the CPU, completely overload it, starve the other VM's and eventually cause them to shutdown.
I'm considering installing vmware server 1.0.5 on this box to compare behaviour.
I do realise my hardware isn't all that great. I'm about to drop in a new core2 duo processor into this machine and I might think about the RAM.
As a point of comparison, I have an ESX 3.5 box with near identical hardware (except for the cpu - it's a core2 duo 2.66GHz) and it runs fine. I brought up a pile of virtual machines two weeks ago and everything worked perfectly.
I realise that vmware server vs esx isn't a valid comparison, but I can't see how vmware server is really usable under these circumstances.