Why use Docker

As an emerging virtualization way, Docker has many advantages compared with the traditional virtualization way.

More efficient use of system resources

Docker has a higher utilization of system resources because the container does not require additional overhead such as hardware virtualization and running a full operating system. Whether it is application execution speed, memory consumption or file storage speed, it is more efficient than traditional VIRTUAL machine technology. Therefore, a host with the same configuration can often run more applications than virtual machine technology.

Faster startup time

Traditional VIRTUAL machine technology usually takes several minutes to start application services, while Docker container applications can be started in seconds or even milliseconds because they run directly in the host kernel and do not need to start the complete operating system. Greatly saving the development, testing, deployment time.

Consistent operating environment

A common problem in development is environmental consistency. Because the development environment, test environment, and production environment are inconsistent, some bugs are not found in the development process. The image of Docker provides a complete runtime environment in addition to the kernel, ensuring the consistency of the application running environment, so that there will no longer be “no problem with this code on my machine”.

Continuous delivery and deployment

The most desirable thing for development and operations (DevOps) people is a single build or configuration that can run anywhere.

With Docker, continuous integration, continuous delivery and deployment can be achieved by customizing application images. Developers can use Dockerfile for image building and Integration testing with Continuous Integration systems, while operations can quickly deploy the image directly into a production environment. Even automatic Deployment with Continuous Delivery/Deployment systems.

Moreover, using Dockerfile to make image construction transparent, not only the development team can understand the application operating environment, but also facilitate the operation and maintenance team to understand the application operating conditions, helping to better deploy the image in the production environment.

Easier migration

Docker ensures the consistency of execution environment, making application migration easier. Docker can run on many platforms, whether physical machine, virtual machine, public cloud, private cloud, or even laptop, and its running results are consistent. Therefore, users can easily migrate an application running on one platform to another without worrying that the application will not run properly due to the change of the operating environment.

Easier maintenance and extension

Docker uses layered storage and image technology, which makes it easier to reuse the repeated parts of the application, easier to maintain and update the application, and it is also very simple to further expand the image based on the basic image. In addition, Docker team maintains a large number of high-quality official images together with various open source project teams, which can be used directly in the production environment and further customized as a basis, greatly reducing the cost of image production of application services.