What are the underlying technologies of docker?

Underlying technology: 1. Namespace, which provides an isolated workspace for containers; 2. Control group, which can limit resources for programs; 3. Joint file system, which supports modification of the file system As a submission, they are layered layer by layer; 4. Container format, which combines namespaces, control groups and joint file systems into a whole called container format.

The operating environment of this tutorial: linux7.3 system, docker-1.13.1 version, Dell G3 computer.

What docker’s underlying technologies are divided into?

Docker uses a series of underlying technologies to give full play to its technical features. These underlying technologies include Namespaces, Control groups, Union file systems and Container. format, etc., their specific meanings are as follows.

1. Namespaces

Docker uses namespaces to provide isolated workspaces for containers. When a container runs, Docker creates a series of namespaces for the container and provides a layer of isolation for the namespaces. Each container runs in a relatively isolated environment and is relatively restricted to other namespaces.

2. Control groups (control groups)

The Docker engine based on Linux systems also relies on another technology called Control groups (cgroups, control groups). The control group can limit the resources of the program and allow the Docker engine to share hardware resources between containers and impose limits and constraints at any time. For example, developers can limit the available memory of a specific container.

3.Union file systems

Union file system (UnionFS) is a layered, lightweight and high-performance file system. It supports file system modifications to be superimposed layer by layer as one submission, and different directories can be mounted to the same virtual file system. Different Docker containers can share some basic file system layers and use them with their own unique modification layers to greatly improve storage efficiency. Docker currently supports joint file systems including AUFS, btrfs, vfs and DeviceMapper.

4.Container format

The Docker engine combines namespaces, control groups, and joint file systems into a whole called a container format. The current default container format is libcontainer. In the future, Docker may develop other container formats through integration with other technologies (such as BSD Jails or Solaris Zones).

Recommended learning: "docker video tutorial"

The above is the detailed content of What are the underlying technologies of docker?. For more information, please follow other related articles on the PHP Chinese website!