Which is the best Virtualization?

In KVM, VPS acts as independent node that is it act like true virtualization.
True virtualization is done in KVM. It acts as independent node in it. There are number of functionalities provided by the KVM and it supports multiple operating systems.

XEN is the isolated, customizable and dedicated solution as it has isolated modules. It provides the virtualized and dedicated memory.

So it totally depend on your requirement which to choose.
 
KVM is full hardware virtualisation, you can run almost any operating system as a guest BSD/Windows/Linux and with virtio driver you will get near native performance, some experiments have shown only 3% loss on native hardware under ideal circumstances.

Xen is a bare metal hypervisor, which makes it capable of running multiple instances of virtual machines on a single host. These hosts are not constrained to the kernel of the host and for that matter do not even have to run Linux in the VPS

OpenVZ is hugely popular in the hosting industry due to its rapid deployment and very high density, it achieves this as the host kernel is shared with the guests along with ram, cpu and disk, with fairly basic separation between guest and host the I/O bottleneck is almost none existent.
 
Before KVM it was XEN, but now KVM many say it as virtual dedicated server so from the name you can understand the power.
 
There's no 'best' virtualization. That said, I only use KVM for my servers. I personally like having control over my resources and kernel.

The only time I use OpenVZ is if I need to spin something up relatively quick, or if the client's budget is limited.
 
Best virtual machine software
1.Parallels Desktop 13.
2.Oracle VM Virtualbox.
3.VMware Fusion and Workstation.
4.QEMU.
5.Red Hat Virtualization.
 
Using a specific technology in virtualization depends on what you want to achieve. So according to your goal, look for one solution which can help you easily and that you can handle more efficiently. VmWare is really good. The only problem is the price. In another hand you have Hyper-V if you use a Windows server (you will just buy the license for the bare metal server). You can now use KVM for open source technologies.
 
The choice of KVM vs. Xen is as likely to be dictated by your vendors as anything else. If you're going with RHEL over the long haul, bank on KVM. If you're running on Amazon's EC2, you're already using Xen, and so on. The major Linux vendors seem to be standardizing on KVM, but there's plenty of commercial support out there for Xen. Citrix probably isn't going away anytime soon.
 
It depends on what your requirements are. If you are using Linux platform, I would suggest looking into the KVM virtualization tool.
 
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