I once asked a wise man in change of a rather large multi-datacenter service, "Have you every considered virtualization?" He replied, "All the CPU's here are pegged at 100%"
They may be applications for this type of processing. I have thought about systems like this from time to time. This thinking goes in circles. Hadoop is designed for storing and processing on different hardware. Virtualization lets you split a system into sub-systems. Virtualization is great for proof of concept. For example, I have deployed this: I installed VMware with two linux systems on my windows host, I followed a hadoop multi-system-tutorial running on two vmware nodes. I was able to get the word count application working, I also confirmed that blocks were indeed being stored on both virtual systems and that processing was being shared via MAP/REDUCE. The processing however was slow, of course this is the fault of VMware. VMware has a very high emulation overhead. Xen has less overhead. LinuxVserver and OpenVZ use software virtualization (they have very little (almost no) overhead). Regardless of how much overhead, overhead is overhead. Personally I find the Vmware falls short of its promises
