Each server gets allocated their pool of resources as configured by the VMWare admin. I would ask your VW admin to get you a list of resources allocated as well as a summary of how the shares are configured (not to be confused with Windows/Samba shares) if they are running Virtual Center. If another virtual server has higher priority shares, then the other servers will give up some memory resources, etc. to allow the higher priority server to process.
I'm a little rusty on this, but that's the general idea. If you have further questions, I would refer you to the VMWare support forums, the guys there are VERY knowledgable.
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