Good programmers Java Training Share Why use Docker, outlined as a way of emerging virtualization, Docker, compared with the traditional approach to virtualization has many advantages.
More efficient use of system resources
Since the container does not require additional hardware virtualization overhead and run a full operating system, higher Docker utilization of system resources. Whether the application execution speed, memory loss or file storage speed, technology should be more efficient than traditional virtual machine. Therefore, compared to virtual machine technology, the same configuration of a host can often run a greater number of applications.
Faster start-up time
The traditional virtual machine technology often takes a few minutes to start the application service, while Docker container application, due to the direct kernel running on the host, without launching a full operating system, it can be done in seconds or even milliseconds of the start-up time. Greatly save development, testing, deployment time.
Consistent runtime environment
The process of developing a common environmental problem is consistency. Because the development environment, test environment, the production environment is inconsistent, resulting in some bug it has not been found during development. The Docker mirroring provides complete run-time environment in addition to the core, to ensure the consistency of the application operating environment, which will not occur again, "this code is no problem on my machine ah" this kind of problem.
Continuous delivery and deployment
The development and operation and maintenance (DevOps) personnel, the most hope is to create or configure once, run anywhere normal.
Use Docker continuous integration can be achieved through custom applications mirroring, continuous delivery, deployment. Developers can Dockerfile that mirror constructed, combined with continuous integration (Continuous Integration) system integration test, the operation and maintenance personnel can quickly deploy the image directly in a production environment, even combine continuous deployment (Continuous Delivery / Deployment) system Auto-deployment.
And the use of Dockerfile the mirror to build transparency, the development team can not understand the application operating environment, convenient operation and maintenance team also understand the conditions needed to run the application, to help better production environments deploy the image.
Easier migration
Since Docker ensure the consistency of the execution environment, making it easier to migrate applications. Docker can run on many platforms, whether it is physical machines, virtual machines, public cloud, private cloud, or even a notebook, its operating results are consistent. So users can run applications on a platform very easily migrate to another platform, without worrying about changes in the operating environment lead to the application not working properly.
Easier to maintain and extend
And tiered storage mirroring technology Docker use, making reuse applications repeat part easier, but also makes applications easier maintenance updates, based on further expansion of the mirror base image becomes very simple. In addition, Docker team with various open source project team to maintain a large number of high-quality official mirror, either in production environments, and can be directly as a basis for further customization, greatly reducing the cost of mirroring application services.
| characteristic |
container |
virtual machine |
| start up |
Second-class |
Minute level |
| Hard drive |
Typically MB |
Typically GB |
| performance |
Near native |
Weaker than |
| System support amount |
Single supports thousands of containers |
General dozens |