Fu Ge answer 2020-09-14: The
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KVM:
1. Virtualization support: full virtualization.
2. Support architecture: virtualized CPU.
3. Kernel support: built into the kernel.
XEN:
1. Virtualization support: full virtualization and paravirtualization.
2. Support architecture: x86, IA64 and ARM from AMD, Fujitsu, IBM, Sun and other companies, as well as x86/64 CPU vendors and Intel embedded support.
3. The kernel needs to be patched.