cgcreate

cgcreate is a command-line utility used in Linux-based systems for creating and managing control groups, often referred to as cgroups. Control groups are a fundamental feature of the Linux kernel that allow for the allocation and partitioning of system resources such as CPU, memory, network bandwidth, and disk I/O among collections of processes. The cgcreate command specifically facilitates the creation of these cgroup hierarchies and the individual cgroups within them.

To use cgcreate, a user typically specifies the name of the controller to be enabled for the new cgroup and the name of the cgroup itself. For instance, a command might look like cgcreate -g cpu,memory:/my_group. This command would create a new cgroup named my_group and associate it with the cpu and memory controllers. Once created, processes can be assigned to this cgroup, and their resource usage will then be governed by the limits or allocations defined for that cgroup through its respective controllers.

The primary purpose of cgcreate is to provide a programmatic way to set up resource management environments. This is particularly useful for system administration tasks, containerization technologies like Docker and LXC, and performance tuning. By creating and configuring cgroups, administrators can ensure that certain applications or services have guaranteed resources or that resource-intensive tasks do not negatively impact other parts of the system. The command acts as an interface to the underlying cgroup filesystem, abstracting some of the direct file manipulation required.