Personally I prefer Xen, because for the suppliers and customers it is acceptable compromise. openvz oversold too much, kvm, etc. to see RP, these twoare not suitable for webmaster who do not want to toss.All right,Let’s move on the difference among them virtual technology creating vps.
1.Openvz.
OpenVZ is operating system-level virtualization technology.Generally means better performance. However, OpenVZ is more flexible configuration set up,which give opportunity that the provider down configuration they marked to black-heart providers.
Advantages: This type of vps is best seller.Licenses are large memory.CPU is also strong, and many sellers, comparability is also very strong.
Disadvantages:Oversold lead to all kinds of stone plate, diamond plate. The associated cpu also lead to over-segmentation performance not as good as its marked appreciation 1/10. Then The memory relied on OpenVZ technology is not exclusive, are shared,others much less you, and the biggest disadvantage is that the server will be down,when the memory is low. Lastly There are a variety of inconvenient to open vpn .
2.Xen
Xen is a paravirtualization technology,.it is not a true virtual machine, but the equivalent of their own to run a kernel instance, free to load the kernel module, virtual memory, and IO, stable and predictable. It part Xen + pv + and Xen + hvm.Only difference is the pv supporting linux, but hvm win support systems.
Advantage: Memory exclusive, a small but guaranteed it assigned to.Part of the virtual technology determine the type of vpbs wont be far oversold which rarely result to stone plate. In addition, Although the memory is low,it will not crash
Disadvantages:compared with the same price and openvz,memory small, hard, small bandwidth.Because of not oversold, in order to make money,only isthree basic configurations dropped down. There is a supplier of defective arrhythmia.Remember pv performance is actually better than the hvm.
3.KVM
Advantages: kvm is completely virtual, so all the kvm + -type class virtualization technology can be fitted with various linux distros and all kinds of win release.
Disadvantages:because kvm can hold any type of operating system, leading to even toss in ram 128m sever equipped with a win2003 (+ directly go after all the cpu and memory are used for hard disk IO, and do not understand why these people want to be ‘God horse’ ). The result is that all the neighbors who have kvm see your neighbors face. To say, if you have four or five ‘God horse’ neighbors.I'm sorry, your hard drive is basically a stone plate