Windows 2008 Memory Caching

[Guest C S S]

We are starting to test Windows 2008 in a virtual environment. We created an

instance of 2008 on top of a VMWare server, and assigned this VM 12GB of ram

for windows (no reserved amount on the host).

 

What we're seeing is that Win 2K8 itself (in performance manager) claims

it's using only 2GB of ram. However it looks like it's keeping 6GB tied up

for cache. Since this is being used, on the host server instead of just 2 GB

being allocated to the VM, it's allocating 8 GB of host memory.

 

My question is, what is this cacheing in 2008, is it like the pre-fetching

in Vista? And is there a way to disable it? We are much less concerned with

performance improvements gained from it caching what it thinks we may want,

than having plenty of available RAM for additional VMs on the host server.