Virtuozzo or KVM: Which Virtualization is Better?

Virtualisation has the great advantage that the same hardware resources can be used for different guest systems. Two popular software solutions are the programs KVM and Virtuozzo. They are mainly used in large data centres or by hosting providers. However, in addition to providing virtual environments, Virtuozzo also offers container solutions. We will clarify what this means and which hypervisor is suitable for which purpose in the following article.

What is KVM?

KVM stands for Kernel-based Virtual Machine and is virtualisation software that is firmly integrated into the Linux kernel from version 2.6.20 onwards. This means that the Linux kernel can be used as a hypervisor itself. It is therefore possible to run multiple operating systems or servers on the same hardware.

Since the Linux kernel itself is licensed under the GPL, KVM is also free for everyone to use. As open-source software, users can view and potentially modify the entire program's source code. Furthermore, KVM as a bare-metal hypervisor is particularly powerful as it can directly access hardware resources without needing an additional software layer.

Various solutions can be used to control the VMs. The most common module is the command-line-based QEMU. However, graphical user interfaces like UCS Virtual Machine Manager are also possible.

The open-source hypervisor KVM gives users great freedom as they can customise the program individually. However, it is important to consider that there is no professional support available if something goes wrong. While the community is happy to help, users ultimately have to take responsibility for all changes to the program and fix any errors independently.

More about KVM servers and some providers of server solutions:

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What is Virtuozzo?

Unlike KVM, Virtuozzo is a commercial program distributed by Parallels Inc., based in Renton, USA. Before 2008, the company was known as SWsoft Inc. The software is available in versions for Linux and Microsoft Windows. The Linux version is based on OpenVZ, an open-source module that adds Linux container-based virtualisations.

Virtuozzo is a Type 1 hypervisor, which means it can also manage hardware resources directly. As such, there are many similarities between KVM and Virtuozzo. In fact, the latter software is built on KVM and utilises many core technologies of the open-source version. Therefore, Virtuozzo is 100% compatible with KVM and enhances its core with additional features.

In addition to server virtualisation, Virtuozzo can also create containers. These are completely isolated from each other and appear as physical servers. In reality, containers utilise the host system's resources more efficiently, allowing more containers to be implemented on the same hardware compared to VMs. Due to the higher efficiency in hardware resource utilisation, it is easier to achieve higher server speeds with containers. However, a downside is that containers are limited to the host's operating system. Therefore, they can only run applications compatible with the host system's OS.

Users considering a container solution for virtualisation should carefully consider on which operating system to set up their VPS hosting and how to secure them.

More about Virtuozzo servers and some providers of server solutions:

Compare Virtuozzo VPS hosting providers

Virtuozzo vs KVM: Which Hypervisor is Better?

For those seeking a simple, flexible, and cost-effective virtualisation solution, KVM is a reliable software. On the other hand, Virtuozzo is its evolution and comes with several additional features. The program excels in

• Developer support,
• improved performance and reduced maintenance effort through container virtualisation, and
• numerous additional applications that can be added through Parallels Inc.

Therefore, Virtuozzo is particularly suitable for demanding users who do not want to compromise on performance and service.

Also, learn about the difference to container virtualisation as in the case of LXC vs KVM.

Our article is based on our own experiences and research as well as information from external sources.

Sources & further links on the topic:
https://www.linux-kvm.org/page/Main_Page (Official Wiki of the KVM community)
https://www.redhat.com/de/topics/virtualization/what-is-KVM (Information from the owner of the KVM developer)
https://www.virtuozzo.com/ (Official Virtuozzo website)
http://download.parallels.com/doc/pvc/PVC_DataSheet_Ltr_EN.pdf (Information on Parallels Virtuozzo Containers)

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Gerd Altmann on Pixabay