To choose the best VPS hosting solution for their company, administrators usually look at hardware resources, compare prices, and search for the best value for their money.
The virtualization technology that powers your server is one of the things that very few webmasters stop to think about when building their websites.
Our objective today will be to examine KVM and OpenVZ, two of the most popular virtualization solutions available on the market, to see how they will impact your hosting services in the future.
What is KVM?
As the name suggests, KVM stands for Kernel-based Virtual Machine and is introduced to the Linux kernel in 2007. There’s nothing more exciting than turning a physical server into a hypervisor with the help of this virtualization module. You can order KVM VPS from here, Linux VPS & Windows VPS.
As a result of using KVM, virtual machines can be created that can run on various operating systems and be completely independent of the host and from one another.
The fact that KVM is available in the Linux kernel and, therefore, free does not mean it lacks any valuable features. Among them are the following:
- CPU hotplug support
- Live server migration
- Dynamic memory management
- VM images support
- Nested guests support
What is OpenVZ?
OpenVZ can be traced back to the late 1990s when it broke ground as a virtualization solution at the operating system level. There was a time when Alexander Tormasov, a member of the team, and Sergey Beloussov, a member of the team, began developing a system that would allow Linux users to create multiple “virtual environments” on the same physical machine.
Containers are the version of these machines that use the host’s kernel but are independent machines with their files, processes, IP addresses, libraries, and so on, even though they use the host’s kernel.
In the same way as KVM, OpenVZ is also a free and open-source virtualization software that has the following key features:
- Low overhead on hardware resources
- Relatively easy setup
- Efficient resource management
- Isolated traffic and firewalling for individual containers
- Health monitoring system
Hardware requirements for KVM vs OpenVZ
Both OpenVZ and KVM offer two distinct types of virtualization, which is why there is such a difference between the two solutions. KVM requires a hypervisor to implement its hardware-level virtualization, which happens to be the server in this case.
To run a hypervisor, you need to have a significant amount of computer power, which means you cannot share the system resources equally between the guest machines.
OpenVZ’s OS-level virtualization eliminates the need for a fully-fledged hypervisor. You can run all the containers by OpenVZ with just a tiny amount of overhead on the host itself.
Based on estimates, it can be said that up to 99% of the physical server’s hardware can be safely distributed between multiple containers.
A comparison of KVM and OpenVZ based on OS support
Thanks to the full virtualization that KVM offers, you can use just about any operating system you want for your virtual machines. Most hosting providers use Linux as their physical server OS. If the company uses KVM virtualization for their physical servers, creating a Windows or FreeBSD VPS would not be a problem.
All containers you create with OpenVZ are packaged as a Linux distribution, and this kernel runs all your containers.
Consequently, to run the containers on a platform other than Linux, there is no option other than to use a Linux container.
Memory distribution between KVM and OpenVZ
In terms of how OpenVZ and KVM distribute the host’s RAM, one of the main differences between the two solutions lies in how they are implemented.
OpenVZ does not limit the amount of memory per virtual machine, whereas KVM has hard limits per virtual machine. OpenVZ’s unused memory is accessible to all containers running on the server.
In most cases, this will not pose too much of a problem, especially if your server doesn’t have a lot of containers running. There is, however, a possibility that if the RAM usage of one of your VPS machines shoots up, it may also adversely impact the performance of the other accounts.
KVM vs OpenVZ – Price
As open-source solutions, both solutions can be downloaded for free and used without any restrictions. You can even install them on your Linux computer at home by downloading and enabling them.
KVM is the more expensive option from a hosting provider’s perspective compared to other virtualization technologies, mainly due to its higher hardware requirements and the more complicated setup process.
Because OpenVZ has a lower overhead and a more straightforward configuration, it has become a favorite among companies looking for budget-friendly solutions due to its lower overhead.
Final Word
They seldom advertise the choice of virtualization technology that hosting companies use. Most of the time, this is because users show relatively little interest in such technicalities. From the point of view of the website owner, this rarely affects the success of their project in any significant way.
As we have learned, the virtualization solution and its correct implementation are crucial to providing a hosting service of the highest quality.