I'm getting this problem too, on a new Mac Pro.
I don't need to switch screen mode at all, I use Unity all the time, though of course the machine does boot in windowed mode at first. I then launch Lotus Notes (which could be significant, as there was a previous problem with it) and that's all I use in the VM all day. Even if I don't actually use the VM at all, and leave it idling, after a time (sometimes as low as 15 minutes, usually 2-3 hours, sometimes longer, and apparently not affected by putting the mac to sleep overnight) VMWare CPU usage goes sky high, and does not recover until the VM is rebooted. Right now, VMWareUser.exe usage from within the VM (which should be idling) says ~30% (System Idle Process is at ~65%, the remaining ~5% is background stuff), whereas the vmware-vmx process on the Mac registers ~160% (it's a two-core VM, therefore flat out would be 200%). If I kill and relaunch VMWareUser.exe within the VM, responsiveness and CPU usage in both VM and Mac drops back to normal (a few percent) for a short time, but the problem returns within a few minutes. The VM is not entirely unresponsive during the problem, but is noticeably slow. It does not appear to relate to screensavers, system sleep, or power saving. I can't see any obvious trigger
1. What guest os are you running (Windows XP / Vista?) What service pack?
XPSP3, installed under Fusion 2.0 beta 2 from a slipstreamed disc.
2. How long is the VM usually running before you notice the problem? Does it happen in 5 minutes / an hour / after you leave it running overnight? Is there anything that makes this more or less likely to happen?
Highly variable, usually longer after a restart, but only a few minutes to an hour or so if I kill VMWareUser.exe and restart it. I haven't been able to tie it down to any known trigger.
3. If you have access to another Windows VM, does it happen with the same frequency on that VM as well?
I have 3 VMs currently.
A: a fairly clean XPSP3 VM set up originally on Fusion 2.0 beta 1 and updated ever since. It has only Office 2007 and Lotus Notes installed, and VMWare Tools are up to date. This has the CPU load problem every day.
B: an almost unused XPSP3 VM set up under VMWare 1.1.3 and upgraded, with various software installed, which is cloned to new machines I set up and then updated to suit (with a new SID). This does not have any known problems, which is why I use it as a basis for others.
C: A conversion of my old Vista PC. This is used only in case I need some registration-sensitive software that I no longer have a code for, and as such I haven't used it enough to know if it has any problems or not under 2.0 final, though it had the same problem under beta 2.
4. What version of tools are you running? You can get this by going to the VMware System tray in the guest os and then going to the about tab.
All XP versions are build 116369. I haven't loaded the Vista VM recently, and it could well be outdated.
I can upload a VMWare Tools log, but there is nothing obviously different after the problem compared to before it happened, and no clear indication of anything changing when it starts.
-Jef.