KVM refers to a virtual machine based on Linux kernel. The biggest advantage of KVM is that it integrates the Linux kernel, so it is very fast. The host operating system of KVM must be Linux, and the supported client operating systems include Linux, Windows, Solaris and BSD. It runs on x86 and x86_64 hardware architectures supporting virtualization expansion, and the cpu supports VT technology.
Xen is an open source virtual machine monitor developed by Cambridge University. The disadvantage of Xen is that the operating system must be explicitly modified ("ported") to run on Xen (but it should provide compatibility for user applications), so it is more troublesome. Xen can achieve high-performance virtualization without special hardware support. The official Linux kernel has removed support for Xen earlier.
VMWare (virtual machine software) is a virtual machine management software of "virtual PC". Its products allow you to run two or more Windows, DOS and LINUX systems on one machine at the same time. Compared with the "multi-boot" system, VMWare adopts a completely different concept. Multi-boot system can only run one system at a time, and the machine needs to be restarted when the system is switched. VMWare is really running at the same time, and multiple operating systems switch on the platform of the main system, just like standard Windows applications. In addition, you can virtually partition and configure each operating system without affecting the data of the real hard disk. You can even connect several virtual machines into a LAN through a network card, which is extremely convenient. The performance of the operating system installed on VMware is much lower than that of the system directly installed on the hard disk, so it is more suitable for learning and testing.
The following table shows KVM, Xen, and VMWare pairs.
Is open source free? Performance advantages and disadvantages?
KVM？ what's up what's up Tall? 1.KVM is a part of the kernel itself, so we can take advantage of kernel optimization and improvement. 2. High performance and stability, without modifying the client system. 3. Open source and free
XEN, right? High 1. Good performance. 2. Open source, free operation and high maintenance cost have been abandoned by RedHat.
VMWare？ No? No? General? Relatively mature commercial software has a large market share, is not open source, and needs to be paid.
If there are 4 cores available, and each core can support up to 8 virtual machines, that's fine.