On Sat, Mar 5, 2011 at 2:05 AM, William Warren hescominsoon@emmanuelcomputerconsulting.com wrote:
I'm curious exactly how KVM works. If i see things right it's virtualization that's still within a full base operating system load correct? How does KVM perform against VMware which uses a much smaller footprint? Is KVM really a hypervisor? I'm just trying figure out the basics of KVM..:)
I have not used VMWare for almost a decade so I unable to make any comments on KVM v/s VMWare; I have used VirtualBox and Linux Kernel Virtual Machine (LKVM).
IMO, the fundamental difference between LKVM and VB:
The LKVM is based upon "qemu" with hardware acceleration. Look for qemu-kvm package (or something similar). It requires hardware support in the motherboard and the CPU (Intel is VT-x || AMD is SVM); otherwise the LKVM modules will not load. The kernel modules create a device as shown:
$ ls -l /dev/kvm crw-rw----+ 1 root kvm 10, 232 Mar 4 10:47 /dev/kvm
Whereas VB can work on any stock x86 hardware. I think the same is true for VMWare as well.
If you want to experiment with LKVM then I would suggest that you first learn the basics through the command line utility qemu-kvm or kvm (depending on the distro) and then graduate to the KVM management tools. You will also need to brush up your knowledge on the Linux bridge utilities and tunctl. Once you get the hang of it, you will find it is quite simple and powerful. I have been deploying LKVM based appliances at client locations since 3Q/2009 - no issues with LKVM thus far.
HTH