A. You might never think about the different types of hypervisor architectures available on the market, but the differentiation is important because different hypervisor architectures have different pros and cons. In IT, two major classes of hypervisors are defined: type 1 and type 2.
Type 1 hypervisors are commonly considered bare metal hypervisors, in that the hypervisor code itself runs directly on top of your hardware. Type 1 hypervisors tend to enjoy much better performance than type 2 hypervisors, due in part to their direct positioning on top of hardware.
Unlike type 1 hypervisors, a type 2 hypervisor must be installed on top of an existing OS. These hypervisors tend to have better hardware compatibility because they use software-based virtualization. For example, you can install a type 2 hypervisor on your laptop much more easily than you could install a type 1 hypervisor. Its drivers are Windows' drivers (or Linux's drivers), which are much greater in number than ESX's, for example.
Performance is the downside with a type 2 hypervisor. Because those hypervisors need to work within the confines of an existing OS, their virtualization performance is limited by the OS's extra software layer. Concurrently-running applications have an effect as well—playing Call of Duty at the same time you're working with a type 2 hypervisor will pull resources from the hypervisor (particularly on some of the more challenging Call of Duty maps).
VMware Workstation is an example of a type 2 hypervisor. You can install it on top of an existing instance of Windows (and a number of Linux distributions). While not considered a fit for production virtual machines, VMware Workstation is great for testing and evaluation situations.
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