KVM and QEMU Explained from the VERDE VDI Perspective

KVM and QEMU Explained from the VERDE VDI Perspective

Product Line:  VERDE

The following provides an explanation of KVM vs. QEMU and how they are used by VERDE VDI.

What is QEMU?

QEMU (https://www.qemu.org) is an open-source hypervisor that performs hardware virtualization. It allows users to run multiple virtual machines, each with its own operating system, on a single physical machine.

QEMU emulates various architectures including x86, ARM, and PowerPC, and can be used for system-level and user-level emulation.

QEMU was first released in 2003.

VERDE VDI RPM distributions include the currently supported QEMU module.


What is KVM?

KVM (Kernel-based Virtual Machine) (https://www.linux-kvm.org/) is a virtualization infrastructure for the Linux kernel that allows multiple operating systems, including Windows and Linux, to run on a single physical machine.

It uses hardware virtualization capabilities, such as Intel VT or AMD-V, to run virtual machines (VMs) with near-native performance. KVM provides a complete virtualization solution for Linux-based systems, including virtual network devices, storage devices, and graphical display capabilities, using supporting components, such as QEMU.

KVM is included in many popular Linux distributions (Ubuntu, Fedora and CentOS) and can be obtained through the distribution's package manager (e.g., yum, apt-get).

KVM was first released in 2006 as part of the Linux kernel, version 2.6.20.

VERDE VDI RPM distributions do not include KVM. The KVM module that comes with the host server Linux distribution is utilized by VERDE VDI.


Who uses KVM?

KVM is widely used by organizations, and cloud service providers for virtualization.

Some of the organizations that use KVM for virtualization include:

· IBM

· Red Hat

· Oracle

· Amazon Web Services (AWS)

· Google Cloud Platform

· Microsoft Azure

· Alibaba Cloud


How does VERDE VDI use QEMU and KVM?

QEMU is invoked directly by VERDE VDI with the appropriate parameters (e.g., HDD type, CPU type, virtual memory allocation, etc.) to launch a virtual machine session.

QEMU is responsible for creating the emulated computer components (e.g., CPU, disk drive, memory, ports, etc.) required by a virtual machine session.

QEMU then directly communicates with KVM to launch the virtual machine session including access to the emulated computer components described above.

KVM is the engine that hosts the virtual machine sessions.

All subsequent data communication between the user and the assigned virtual machine session is processed through the VERDE VDI Connection Broker to QEMU which then interfaces with KVM.



Benefits of QEMU and KVM

QEMU emulates required computer components such as CPU, disk drive, memory, ports, etc. QEMU includes direct integration with KVM to provide access to the emulated components.

KVM utilizes x86 hardware virtualization extensions (Intel VT or AMD-V) providing superior performance of the virtual machine sessions.

The key differentiating factor is that KVM is kernel level while QEMU is a user level application. This provides KVM with much better performance for running the virtual machine session.

QEMU allows VERDE VDI to communicate with KVM and implement virtualized devices that the virtual machine sessions require.

    • Related Articles

    • FAQ: VERDE 8.2 Frequently Asked Questions.

      VERDE 8.2 FAQs:   What’s new in VERDE 8.2? VERDE 8.2 is our latest VERDE-VDI offering and has been upgraded to use the latest Red Hat / CentOS QEMU-KVM modules for increased performance and hardware emulation capabilities.  This means that we are now ...

    • VERDE VDI Session WorkFlow

      Product Line:  VERDE The following diagram displays the VDI Session Workflow:

    • Running VERDE (CM/MC/VDI) on a vSphere - VMWARE ESX server

      Product Line:  VERDE The ESX server is capable of doing nested virtualization, so it's possible to run VERDE servers that run VDI sessions on this ESX host. You must enable the "vhv.enable=TRUE" flag in the .vmx file to take advantage of this ...

    • Choosing the Right VERDE Install Instructions with Postgres Database (Centos7)

      Product Line: VEREDE As of VERDE 8.3.4, the database POSTGRES is used. The database is much more nimble and efficient. Due to the new database, there are design changes that need to be explained. If the customer plans to only install VERDE on one ...

    • VERDE VDI Optimization for Windows 10

      Product Line:  VERDE   Introduction   A basic Windows 10 ISO is not configured by default for VDI implementation.  If not configured correctly, a Windows 10 guest will consume a a large amount of CPU, Memory and network resources per desktop. The ...