Kernel-based Virtual Machine

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Kernel-based Virtual Machine
Screenshot
Screenshot of qemu/kvm running NetBSD, OpenSolaris and Kubuntu on an Arch Linux host.
Stable release 88 / July 14, 2009; 8 months ago (2009-07-14)
Written in C
Operating system Linux kernel
Type Platform virtualization
License GNU General Public License or GNU Lesser General Public License
Website http://www.linux-kvm.org/

Kernel-based Virtual Machine (KVM) is a Linux kernel virtualization infrastructure. KVM currently supports native virtualization using Intel VT or AMD-V. Limited support for paravirtualization is also available for Linux guests and Windows in the form of a paravirtual network driver,[1] a paravirtual block I/O device (disk) driver,[2] a balloon driver to affect operation of the guest virtual memory manager,[3] and CPU optimization for Linux guests.

Architecture ports are currently being developed for s390,[4] PowerPC,[5] and IA64.[clarification needed] The first version of KVM was included in Linux 2.6.20 (February 2007).[6] KVM has also been ported to FreeBSD as a loadable kernel module.[7]

A wide variety of guest operating systems work with KVM, including many flavours of Linux, BSD, Solaris, Windows, Haiku, ReactOS and AROS Research Operating System[8] and a patched version of kvm is able to run Mac OS X.[9]

Contents

[edit] Design and licensing

By itself, KVM does not perform any emulation. Instead, a user-space program uses the /dev/kvm interface to set up the guest VM's address space, feeds it simulated I/O and maps its video display back onto the host's. At least two programs exploit this feature: a modified version of Qemu and Qemu itself since version 0.10.0.

KVM's parts are licensed under various GNU licenses:[10]

  • KVM kernel module: GPL v2
  • KVM user module: LGPL v2
  • QEMU virtual CPU core library (libqemu.a) and QEMU PC system emulator: LGPL
  • Linux user mode QEMU emulator: GPL
  • BIOS files (bios.bin, vgabios.bin and vgabios-cirrus.bin): LGPL v2 or later

KVM is maintained by Avi Kivity and is funded primarily by Qumranet, a technology start up,[11] now owned by Red Hat.[12]

[edit] Graphical management tools

  • Virtual Machine Manager supports creating, editing, starting, and stopping KVM based virtual machines.
  • ConVirt supports creating, editing, starting, and stopping KVM based virtual machines, as well as live or cold drag-and-drop migration of VMs between hosts.
  • Proxmox Virtual Environment Free virtualization software including KVM and OpenVZ - bare-metal installer, management GUI and optional commercial support.

[edit] Emulated hardware

Class Device
Video card VGA[13]
Sound card Sound Blaster 16[14]
Ethernet Network card AMD Am79C970A (and Am7990?)[15], E1000 (Intel 82540EM, 82573L, 82544GC) [16], NE2000[17], Realtek 8139[18]

[edit] See also

Free software portal

[edit] References

  1. ^ Gmane - Mail To News And Back Again
  2. ^ libvirt: Wiki: Virtio
  3. ^ 3.2 Ballooning
  4. ^ Gmane - Mail To News And Back Again
  5. ^ Gmane Loom
  6. ^ "Linux: 2.6.20 Kernel Released". KernelTrap. http://kerneltrap.org/node/7670. 
  7. ^ "FreeBSD Quarterly Status Report: Porting Linux KVM to FreeBSD". http://www.freebsd.org/news/status/report-2007-07-2007-10.html#Porting-Linux-KVM-to-FreeBSD. 
  8. ^ "KVM wiki: Guest support status". http://www.linux-kvm.org/page/Guest_Support_Status. Retrieved 2007-05-27. 
  9. ^ "Virtualizing an x86 Mac OS X". http://alex.csgraf.de/self/?part/projects&folder/Qemu%20OSX&type/&project/projects&parameters/id=Qemu%20OSX. 
  10. ^ Licensing info from Ubuntu 7.04 /usr/share/doc/kvm/copyright
  11. ^ Interview: Avi Kivity on KernelTrap
  12. ^ Red Hat press release on Qumranet purchase
  13. ^ kvm-85/qemu/hw/vga.c
  14. ^ kvm-85/qemu/hw/sb16.c
  15. ^ kvm-85/qemu/hw/pcnet.c
  16. ^ kvm-85/qemu/hw/e1000.c
  17. ^ kvm-85/qemu/hw/ne2000.c
  18. ^ kvm-85/qemu/hw/rtl8139.c

[edit] External links

Retrieved from "http://en.wikipedia.org/wiki/Kernel-based_Virtual_Machine"