The most evident and important diff between a HyperVisor and VMware (simillar products) is that Hypervisor is a Technology and VMware and Microsoft Virtual PC are applictions. We can call Hypervisor as an OS that runs directly on a bare-hardware. In contrast products like Microsoft Virtual PC and VMware requires an OS to run on. Once an OS(windows\Linux) is insatalled on Hardware, you can install these products on the OS and then can utilize these products to run various OS. However unlike VMware software HyperVisor runs directly on Bare-Hardware..without the OS. U can think HyperVisor as a BIOS, which is intalled on the Hardware.
Because VMware Server is burdened with the I/O overhead of an existing OS, it is not as efficient as a bare-metal hypervisor. On the other hand, it has a broad driver compatibility because VMware Server can use every hardware device compatible with the host OS. A bare-metal hypervisor typically supports only a limited number of devices since its control OS's kernel is not compiled with many device drivers (in order to keep the kernel small and fast).
Xen is special -- it is a bare-metal hypervisor, but it is designed such that it has broad hardware device compatibility. It relies upon driver domain operating systems, typically the OS in dom-0, but not necessarily, to provide device drivers
No comments:
Post a Comment