The Xen VMM. Nathanael Thompson and John Kelm. Motivations. Full virtualization of x86 is hard and imperfect Instead, make hosted OS aware of virtualization but not hosted applications Enable performance isolation and accounting. Outline. Motivations The Xen Implementation
(40% of hypervisor time, says Intel)
1. Privileged Instruction
5. Return From Interrupt
3. Trap and…
4. …Emulate Instruction
Why not just paravirtualize?
x86 Protection Mechanisms
2. Protection Fault!
Is this a more fair comparison of VMs?
What does it tell us about HW-assisted full virtualization versus paravirtualization?