What is hypervisor? What is the difference between type 1 and type 2?

In understanding Type 1 and Type 2 Hypervisor And which is better before , Let's see first Hypervisor What is it? ？

What is? Hypervisor？

Hypervisor It's a kind of system software , It acts as an intermediary between the computer hardware and the virtual machine , Responsible for effectively allocating and utilizing the hardware resources used by each virtual machine , These virtual machines work independently on the physical host , therefore ,Hypervisor Also known as virtual machine manager .

Hypervisor It consists of three main modules ：

The dispenser Dispatcher

It forms the entry point for the monitor , And reroute the instructions issued by the virtual machine instance to the allocator or interpreter module described below .

distributor Allocator

Whenever a virtual machine attempts to execute an instruction that results in a change in the relevant machine resources , The allocator will be called by the scheduler , The allocator then provides the system resources to the virtual machine .

Interpreter Interpreter Routines

It consists of interpreter routines , These routines are executed whenever the virtual machine executes privileged instructions , This is also called by the dispatcher .

Now let's see Hypervisor And the differences between them .

Type 1 Hypervisor

Can be installed locally and run directly on the physical host Hypervisor be called Type 1 Hypervisor.

Key indicators

• Type 1 Hypervisor It can be installed directly on bare metal systems or physical hosts .
• It does not require an operating system to be installed or available (OS), You can deploy yourself on the server .
• Direct access CPU、 Memory 、 The Internet 、 Physical storage .
• More efficient use of hardware , Provide the best performance .
• Since there is no additional hardware access layer , So it's safer .
• Every Type 1 Hypervisor Always need a dedicated physical machine .
• Can be more expensive , More suitable for enterprise class solutions .
• VMware ESXi、Citrix Hypervisor and Microsoft Hyper-V yes Type 1 Hypervisor Some examples of .

Type 2 Hypervisor

A hypervisor that cannot be installed locally and requires an operating system to run on a physical host is called a type 2 Management procedure .

Key indicators

• Type 2 hypervisor It cannot be installed directly on bare metal systems or physical hosts .
• It requires the operating system installed or available first , To deploy yourself .
• Indirect access to CPU、 Memory 、 The Internet 、 Physical storage .
• Due to the need for additional layers (OS) To access resources , As a result, hardware utilization may decrease and lead to performance lag .
• Due to the availability of the host operating system , Potential security risks .
• Every Type 2 hypervisor No special physical machine is required . There can be multiple on a single host .
• A lower cost , More suitable for small business solutions .
• VMware Workstation Player、VMware Workstation Pro and VirtualBox yes Type 2 hypervisor Some examples of .

Conclusion

Hopefully these key metrics will help you in both types of Hypervisor Make a decision between , According to use case scenarios , You used Hypervisor Of course, the type will change from time to time .

For enterprise level requirements , type 1 Is a way to satisfy most preferences , And type 2 It is helpful when the operating system on the host may also need to meet other requirements .