May 22, 2021 Docker From entry to practice
As an emerging form of virtualization, Docker has many advantages over traditional virtualization.
First, the Docker container can be started in seconds, much faster than traditional virtual machine methods. Second, Docker is highly utilized for system resources, with thousands of Docker containers running on a host at the same time.
Containers, in addition to running their applications, basically do not consume additional system resources, making the performance of the application very high, while the system overhead is as small as possible. Running 10 different applications in a traditional virtual machine mode requires 10 virtual machines, while Docker only needs to start 10 isolated apps.
Specifically, Docker has a big advantage in the following areas.
For development and operations (devop) personnel, the most promising thing is to create or configure it once and work anywhere.
Developers can use a standard image to build a development container that operations personnel can use directly to deploy code when development is complete. D ocker can quickly create containers, iterate the application quickly, and make the entire process visible, making it easier for other members of the team to understand how the application was created and worked. D ocker containers are light and fast! Container start-up time is second-class, saving a lot of time to develop, test, and deploy.
Docker containers run without additional hypervisor support, which is kernel-level virtualization and therefore achieves greater performance and efficiency.
Docker containers can run on virtually any platform, including physical machines, virtual machines, public clouds, private clouds, personal computers, servers, and more. This compatibility allows users to migrate one application directly from one platform to another.
With Docker, only minor modifications are required to replace the large amount of update work that has been done in the past. All modifications are distributed and updated incrementally for automated and efficient management.
| Characteristics | Container | The virtual machine |
|---|---|---|
| Start | Second level | Minute level |
| Hard drive use | Typically MB | Typically GB |
| Performance | Close to native | weaker than |
| The amount of system support | Thousands of containers are supported on a stand-alone computer | Generally dozens |