Containerization is a type of virtualization at the application level, which allows for multiple isolated user space instances on a single kernel. These instances are called containers.
Containers provide a standard method of packaging an application's code, runtime, system tools, system libraries, and configurations into one instance. Containers share one kernel (operating system), which is installed on the hardware.
Benefits of Containers
Containers take up a smaller amount of space on the server than virtual machines, and typically take only a few seconds to start up.
Containers are highly elastic and don’t need to be allocated a given amount of resources. This means containers are able to make more efficient and dynamic use of the resources from the server. When the demand on one container decreases, the extra resources are freed to be used by other containers.
Density refers to the number of objects that a single physical server can run at a time. Containerization allows the creation of dense environments in which the host server’s resources are fully utilized but not over-utilized. Compared with traditional virtualization, containerization allows for more dense environments because containers do not need to host their own operating system.
When there is high resource pressure, the performance of applications is far better with containers than it is with hypervisors. Because with traditional virtualization, the guest OS must also meet its own memory needs, taking valuable RAM away from the host.
- Maintenance Efficiency
With only one operating system kernel, updates or patches on the operating system level only needs to be done once for changes to take effect across all containers. This makes the operations and maintenance of servers more efficient.
What Is Container Orchestration?
The deployment and organization of containers to support applications is called container orchestration, which is done through a container orchestration tool. Some popular open source container orchestration tools include Kubernetes, Docker Swarm, and LXC.
When to Use Containers?
Almost any application that needs to change and re-deploy quickly and frequently is a good fit for containerization. Applications using a Microservices Architecture are also a natural choice.
Alibaba Cloud provides Container Service for Kubernetes
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