KVM What is?

What is KVM? Features, Advantages, and Use Cases

KVM (Kernel-based Virtual Machine) is an open-source virtualization technology that operates on the Linux kernel. First released in 2007, KVM allows users to create multiple virtual machines on a single physical server. These virtual machines can run their own operating systems and share the physical hardware, enabling efficient resource usage.
In this article, you will learn detailed information about KVM, how it works, its advantages, and its use cases.

What is KVM?

KVM is a virtualization solution integrated into the Linux kernel, widely used in high-performance virtualization projects. KVM allows each virtual machine to install and run its own operating system. These virtual machines (VM) use the physical server’s CPU, RAM, storage, and network resources. Additionally, KVM supports not only Linux operating systems but also Windows and other UNIX-based systems.
KVM provides high performance by utilizing hardware-based virtualization technologies. This feature is activated on processors with virtualization extensions such as Intel VT-x and AMD-V. When used in conjunction with QEMU (Quick Emulator), KVM allows virtual machines to run at full hardware speed.

Key Features of KVM

Here are some standout features of KVM:

1. Open Source

KVM is an open-source virtualization solution, meaning it is continuously updated and developed by a large global developer community. Users can customize KVM to meet their needs and use it at a lower cost compared to commercial virtualization software.

2. High Performance

Since KVM is kernel-based, it offers higher performance compared to other virtualization solutions. It works with processor virtualization extensions, providing hardware-speed performance in virtual machines.

3. Flexibility and Scalability

KVM is suitable for both small-scale and large-scale data centers. It can run hundreds or even thousands of virtual machines in large server clusters. Its flexible structure allows you to run different operating systems as virtual machines.

4. Full Hardware Support

KVM offers the best performance on processors that support hardware-based virtualization. Thanks to virtualization extensions like Intel VT-x and AMD-V, virtual machines can run almost as fast as physical machines.

5. Security

Since KVM runs on the Linux kernel, it inherits Linux’s security features. It integrates with security modules like SELinux and AppArmor. Additionally, each virtual machine operates in a separate user space, so an issue in one virtual machine does not affect others.

Advantages of KVM

KVM offers many advantages compared to other virtualization solutions. Here are some of them:

1. Low Cost

KVM is significantly more cost-effective compared to commercial virtualization solutions. Being open-source, it offers an economical virtualization solution, especially for small and medium-sized businesses.

2. High Performance and Efficiency

KVM can run virtual machines at full performance on physical hardware. Since it is a kernel-based virtualization solution, resource usage is highly efficient.

3. Wide Operating System Support

KVM is not limited to Linux. You can run Windows, macOS, and other UNIX-based operating systems as virtual machines. This flexibility is one of the main reasons KVM is preferred in various projects.

4. Easy Management

KVM simplifies the management of virtual machines. Advanced users can manage virtual machines through the command-line interface, while new users have graphical management tools available. Tools like Virt-Manager make it easy to create and manage virtual machines.

Use Cases of KVM

KVM has a wide range of use cases in different fields. Here are some important ones:

1. Data Centers

KVM is widely used in large-scale data centers. Server virtualization increases the efficiency of physical servers and reduces costs. By running multiple virtual machines on the same physical server, resources can be used more effectively.

2. Testing Environments

KVM is ideal for developers and software testing teams. You can quickly create virtual machines to test different operating systems and software configurations. This allows you to see how software performs on various platforms.

3. Cloud Services

KVM is used as a virtualization platform by many cloud providers. Its flexibility, security, and high performance make it a preferred choice for cloud-based infrastructures. Solutions like OpenStack are built on top of KVM.

Conclusion

KVM offers a powerful, flexible, and economical solution among virtualization technologies. Its open-source structure, high performance, and wide range of use cases make it an ideal virtualization platform, especially for Linux-based data centers and server infrastructures. When used with processors supporting hardware-based virtualization, KVM allows virtual machines to run almost as fast and reliably as physical machines.