KVM, which stands for Kernel-based Virtual Machine, is an open-source software platform that enables virtualization for x86 and other server platforms running the Linux operating system (OS) and can be loaded to run multiple virtual machines on a single server running unmodified Linux or Windows.
KVM has become one of the most widely used virtualization technologies today, and it has taken on many different forms by companies or organizations that have modified the code, including IBM and Red Hat. It is an open-source alternative to proprietary virtualization technologies such as ESXi offered by VMware and Microsoft. Other open-source virtualization solutions include Xen, which is supported by Citrix.
History of KVM
Israeli startup Qumranet built KVM, and software engineer Avi Kivity is widely attributed as a primary developer of the early versions. Qumranet was acquired by Red Hat in 2008 for close to $100 million. The original platform supported x86 processors but it was later ported to other chip platforms including 2/390 and ARM. It is licensed under the GNU license and is currently maintained by Paolo Bonzini and Gleb Natapov.
KVM has ridden the virtualization wave as one of many popular virtualization solutions. In an array of market-research reports, it runs #3 or #4 in market share for hypervisor virtualization, usually behind VMware (#1) and Hyper-V (#2).
The challenge for KVM, as with many virtualization products, has been to compete with the dominance of VMware’s vSphere product in data-center installations. It does have an edge being the preferred hypervisor for OpenStack, but VMware’s further integration of ESXi with OpenStack shows that it’s going to fight in that market as well. It does face challenges in battling VMware, which is the giant in the hypervisor market. The commercial software provider has significant resources, and it has been expanding its efforts in OpenStack and network virtualization.
As an open-source platform, KVM can be favored by those that don’t want to be locked into a commercial hypervisor. Fans of KVM say that in many cases, it can be cheaper to implement. It also tends to be more popular in Linux environments whereas Hyper-V and VMware’s vSphere would be used more heavily in Windows environments.