Blogs

Published At Last Updated At
Bhavesh Gawade
Bhavesh GawadeSoftware Engineerauthor linkedin

Docker vs Virtual Machines

Docker vs Virtual Machine

What are virtual machines?

A virtual machine (VM) is a computing environment created atop a physical machine using software, rather than relying on a dedicated physical computer. It enables the execution of programs and delivery of applications virtually. Within this setup, one or more virtual "guest" computers operate on the underlying physical "host" computer. Each virtual machine functions with its own operating system and remains isolated from other virtual machines, even when they share the same host.


What is the purpose of virtual machines?

Virtual machines are handy for different needs like running programs with varying power needs, using software that requires different features, and testing applications in a safe area. They rely on Hypervisor to make these virtual machines.


What is a hypervisor?

The hypervisor allows the host computer to support multiple virtual machines by sharing their resources, such as memory and processing power.


What is docker?

docker-image

Docker is a software program platform that allows you to build, check, and set up programs quickly. Docker programs software programs into standardized units referred to as containers which have the whole thing the software wishes to run which include libraries, system tools, code, and runtime. using Docker, you may quickly install and scale programs into any environment and know your code will run.

Docker offers builders and admins an exceedingly dependable, low-cost way to construct, deliver, and run distributed applications at any scale.


Why use Docker?

Using Docker lets you deliver code quicker, standardize utility operations, seamlessly circulate code, and save money by way of improving useful resource usage.

With Docker, you get a single item that can reliably run everywhere. Docker's simple syntax gives you complete control over the application.


What is Container?

A container is a standalone, executable package of software that includes everything needed to run an application: code, runtime, system tools, system libraries, and settings. Containers isolate software from its surroundings, for example, differences between development and staging environments, and help reduce conflicts between teams running different software on the same infrastructure.


Container vs hypervisor

Containers and hypervisors both play roles in enhancing application performance and efficiency, but they operate differently.

Hypervisors:

  • Let the operating system work separately from the physical hardware by using virtual machines.
  • Share resources like computing power, storage, and memory among virtual machines.
  • Enable running multiple operating systems on one server or isolating them from a single standard operating system (known as a hosted hypervisor).

Containers:

  • Allow applications to run independently of the operating system.
  • They can run on any operating system - just need a container engine to run.
  • They are extremely portable because the container contains everything the application needs to run.

Hypervisors and containers serve distinct purposes. Hypervisors create and manage virtual machines (VMs), each running its own complete operating system, securely separated from others. On the other hand, containers contain solely the application and its related services. This lightweight nature makes containers highly portable, facilitating rapid and flexible application development and deployment.


Difference between docker and virtual machine

image here

Difference 

Docker

Virtual Machine

Operating system

Docker employs a container-based approach, utilizing software packages known as containers to execute applications across various operating systems. Within Docker, these containers leverage the host OS kernel, enabling multiple workloads to operate on a single OS simultaneously.

It utilizes both user space and kernel space within an operating system. It doesn't share the host kernel. Instead, each workload requires its own complete OS or hypervisor.

Performance

Docker containers deliver high performance by leveraging the same operating system without the need for additional software like a hypervisor. They also offer quick startup times, reducing overall boot-up time.

Virtual machines consume more resources because they require a separate operating system. Additionally, they tend to have slower startup times, which can result in poorer performance compared to Docker containers.

Portability

Using Docker containers, individuals can develop an application, package it into a container image, and then deploy it across various host environments seamlessly. Docker containers are smaller compared to virtual machines, simplifying the process of transferring files within the host's file system.

Virtual machines, on the other hand, lack a central hub and demand more memory space for data storage. When transferring files, VMs necessitate a copy of the entire operating system and its dependencies, leading to larger image sizes and a cumbersome data-sharing process.

Speed

Applications within Docker containers start promptly because the operating system is already up and running. Docker containers were primarily designed to streamline the application deployment process, saving considerable time.

Deploying a single application with Virtual Machines takes significantly longer compared to containers because VMs need to initiate the entire operating system, which entails a full boot process. This contrasts with containers, which can run applications much more swiftly.

Runs On

Dockers make use of the execution engine.

VM make use of the hypervisor.

Conclusion

Docker and virtual machines serve distinct purposes.

  • Virtual machines are still valuable, particularly in complex setups where system integrity is paramount.
  • Docker excels in application testing and offers diverse setups for software experimentation.
  • Docker containers are smaller and faster compared to virtual machines because they share components with the main system.
  • Many companies use both Docker and virtual machines, leveraging each technology based on specific needs.
  • While some prefer virtual machines due to familiarity, others choose Docker for its flexibility and security benefits.
  • Virtual machines are well-suited for stable environments, while Docker's agility facilitates updates and flexibility.
  • Both technologies have their strengths and complement each other in modern computing environments.