KVM

KVM (Kernel Virtual Machine) is a Linux kernel module that allows a userspace program to utilize the hardware virtualization features of various processors. Today, it supports recent Intel and AMD chips, PPC 440, PPC 970, and S/390 processors.

QEMU can make use of KVM when simulating the target architecture is the same as the host architecture. For instance, when running qemu-system-x86 on an Intel processor, you can take advantage of KVM acceleration.

http://wiki.qemu.org/KVM

KVM (for Kernel-based Virtual Machine) is a full virtualization solution for Linux on x86 hardware containing virtualization extensions (Intel VT or AMD-V). It consists of a loadable kernel module, kvm.ko, that provides the core virtualization infrastructure and a processor specific module, kvm-intel.ko or kvm-amd.ko. KVM also requires a modified QEMU although work is underway to get the required changes upstream.

Using KVM, one can run multiple virtual machines running unmodified Linux or Windows images. Each virtual machine has private virtualized hardware: a network card, disk, graphics adapter, etc.

The kernel component of KVM is included in mainline Linux, as of 2.6.20.

KVM is open source software.

http://www.linux-kvm.org/page/Main_Page