KVM vs LXC

Overview

KVM

Stacks189

Followers234

Votes8

LXC

Stacks116

Followers223

Votes19

GitHub Stars5.0K

Forks1.2K

KVM vs LXC: What are the differences?

KVM (Kernel-based Virtual Machine) and LXC (Linux Containers) are two popular virtualization technologies used to create and manage isolated environments on a single physical host. Here are the key differences between KVM and LXC:

Virtualization Type: KVM is a hardware-level virtualization technology that uses a hypervisor to create and manage virtual machines (VMs) with their own operating systems and kernels. On the other hand, LXC is an OS-level virtualization method that utilizes Linux's containerization features to run multiple isolated user spaces on a shared kernel.
Isolation Level: KVM provides strong isolation between VMs as each VM runs with its own virtualized hardware components and operates as an independent system. LXC offers a lower level of isolation since containers share the host's kernel, potentially leading to less isolation between applications.
Resource Utilization: KVM consumes more resources as it emulates complete hardware components and requires separate kernels for each VM, resulting in higher resource overhead. LXC is more resource-efficient as containers share the host's kernel and utilize fewer resources, leading to faster startup times and efficient memory utilization.
Performance: KVM offers good performance and is suitable for running various operating systems and workloads. LXC provides superior performance for Linux-based applications since it avoids the overhead of emulating hardware components and running multiple kernels.
Portability: KVM provides higher portability due to its ability to run different operating systems and applications in isolated VMs. LXC containers are more suited for applications designed to run within Linux environments, limiting their portability to other operating systems.
Use Cases: KVM is suitable for scenarios requiring complete isolation, compatibility with various operating systems, and the need to run legacy applications. LXC is ideal for lightweight containerization of Linux applications, microservices, and cloud-native environments, emphasizing efficiency and rapid deployment.
Ecosystem and Tooling: KVM is supported by various management tools and platforms, including libvirt and tools integrated into popular virtualization platforms. LXC benefits from a rich ecosystem of container management tools like Docker, Kubernetes, and container orchestration frameworks.
Security: KVM offers better security through complete isolation between virtual machines. LXC's security relies on the shared kernel, potentially raising security concerns when hosting untrusted applications.
Overhead: KVM introduces higher overhead due to the need to emulate hardware components and run separate kernels for each VM. LXC has lower overhead since it shares the host's kernel and requires fewer resources for containerization.

In summary, KVM provides strong isolation and compatibility, making it suitable for diverse workloads, while LXC excels in efficiency and speed for Linux-based applications.

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Detailed Comparison

KVM	LXC
KVM (for Kernel-based Virtual Machine) is a full virtualization solution for Linux on x86 hardware containing virtualization extensions (Intel VT or AMD-V).	LXC is a userspace interface for the Linux kernel containment features. Through a powerful API and simple tools, it lets Linux users easily create and manage system or application containers.
Statistics
GitHub Stars -	GitHub Stars 5.0K
GitHub Forks -	GitHub Forks 1.2K
Stacks 189	Stacks 116
Followers 234	Followers 223
Votes 8	Votes 19
Pros & Cons
Pros 4 No license issues 2 Flexible network options 2 Very fast	Pros 5 Easy to use 4 Lightweight 3 Simple and powerful 3 Good security 2 LGPL

What are some alternatives to KVM, LXC?

Docker

The Docker Platform is the industry-leading container platform for continuous, high-velocity innovation, enabling organizations to seamlessly build and share any application — from legacy to what comes next — and securely run them anywhere

VirtualBox

VirtualBox is a powerful x86 and AMD64/Intel64 virtualization product for enterprise as well as home use. Not only is VirtualBox an extremely feature rich, high performance product for enterprise customers, it is also the only professional solution that is freely available as Open Source Software under the terms of the GNU General Public License (GPL) version 2.

LXD

LXD isn't a rewrite of LXC, in fact it's building on top of LXC to provide a new, better user experience. Under the hood, LXD uses LXC through liblxc and its Go binding to create and manage the containers. It's basically an alternative to LXC's tools and distribution template system with the added features that come from being controllable over the network.

Proxmox VE

It is a complete open-source platform for all-inclusive enterprise virtualization that tightly integrates KVM hypervisor and LXC containers, software-defined storage and networking functionality on a single platform, and easily manages high availability clusters and disaster recovery tools with the built-in web management interface.

VMware vSphere

vSphere is the world’s leading server virtualization platform. Run fewer servers and reduce capital and operating costs using VMware vSphere to build a cloud computing infrastructure.

rkt

Rocket is a cli for running App Containers. The goal of rocket is to be composable, secure, and fast.

Qemu

When used as a machine emulator, it can run OSes and programs made for one machine (e.g. an ARM board) on a different machine (e.g. your own PC). By using dynamic translation, it achieves very good performance. When used as a virtualizer, it achieves near native performance by executing the guest code directly on the host CPU. it supports virtualization when executing under the Xen hypervisor or using the KVM kernel module in Linux. When using KVM, it can virtualize x86, server and embedded PowerPC, 64-bit POWER, S390, 32-bit and 64-bit ARM, and MIPS guests.

Parallels Desktop

Parallels Desktop for Mac allows you to seamlessly run both Windows and MacOS applications side-by-side with speed, control and confidence.

Vagrant Cloud

Vagrant Cloud pairs with Vagrant to enable access, insight and collaboration across teams, as well as to bring exposure to community contributions and development environments.

Parallels

It is an application and desktop virtualization software vendor that offers management and delivery platforms for Apple macOS and Microsoft Windows desktop deployments.

Related Comparisons

Virtualization Type: KVM is a hardware-level virtualization technology that uses a hypervisor to create and manage virtual machines (VMs) with their own operating systems and kernels. On the other hand, LXC is an OS-level virtualization method that utilizes Linux's containerization features to run multiple isolated user spaces on a shared kernel.
Isolation Level: KVM provides strong isolation between VMs as each VM runs with its own virtualized hardware components and operates as an independent system. LXC offers a lower level of isolation since containers share the host's kernel, potentially leading to less isolation between applications.
Resource Utilization: KVM consumes more resources as it emulates complete hardware components and requires separate kernels for each VM, resulting in higher resource overhead. LXC is more resource-efficient as containers share the host's kernel and utilize fewer resources, leading to faster startup times and efficient memory utilization.
Performance: KVM offers good performance and is suitable for running various operating systems and workloads. LXC provides superior performance for Linux-based applications since it avoids the overhead of emulating hardware components and running multiple kernels.
Portability: KVM provides higher portability due to its ability to run different operating systems and applications in isolated VMs. LXC containers are more suited for applications designed to run within Linux environments, limiting their portability to other operating systems.
Use Cases: KVM is suitable for scenarios requiring complete isolation, compatibility with various operating systems, and the need to run legacy applications. LXC is ideal for lightweight containerization of Linux applications, microservices, and cloud-native environments, emphasizing efficiency and rapid deployment.
Ecosystem and Tooling: KVM is supported by various management tools and platforms, including libvirt and tools integrated into popular virtualization platforms. LXC benefits from a rich ecosystem of container management tools like Docker, Kubernetes, and container orchestration frameworks.
Security: KVM offers better security through complete isolation between virtual machines. LXC's security relies on the shared kernel, potentially raising security concerns when hosting untrusted applications.
Overhead: KVM introduces higher overhead due to the need to emulate hardware components and run separate kernels for each VM. LXC has lower overhead since it shares the host's kernel and requires fewer resources for containerization.

In summary, KVM provides strong isolation and compatibility, making it suitable for diverse workloads, while LXC excels in efficiency and speed for Linux-based applications.

KVM vs LXC