KVM will be included in Linux kernel 2.6.20

Quoting from Heise Online:

Linus Torvalds has included the virtualization environment KVM (Kernel-based Virtual Machine for Linux) in the tree leading to Linux kernel 2.6.20. In the case of KVM the kernel after loading a special module itself functions as a hypervisor for virtual machines.

KVM, which was presented to the public only barely two months ago, thereby easily overtakes other virtualization solutions such as Xen, OpenVZ and Vserver, which are based on other approaches, on the path toward integration into the kernel.

Read the whole article at source.

The original patch announcement discloses some details about current KVM status:

SMP hosts and UP guests are supported. At the moment only Intel hardware is supported, but AMD virtualization support is being worked on.

Performance currently is non-stellar due to the naive implementation of the mmu virtualization, which throws away most of the shadow page table entries every context switch. We plan to address this in two ways:

  • cache shadow page tables across tlb flushes
  • wait until AMD and Intel release processors with nested page tables

Currently a virtual desktop is responsive but consumes a lot of CPU. Under Windows I tried playing pinball and watching a few flash movies; with a recent CPU one can hardly feel the virtualization. Linux/X is slower, probably due to X being in a separate process…

More details about KVM are available at the official site.