All About the Linux Kernel: Cgroup’s Redesign
Over the past few months, big changes have been underway on the cgroup Linux kernel subsystem and its related, but independent, system and service manager Systemd. Developers aren’t building shiny new features, though, as much as overhauling cgroups (control groups) to impose more structure in an area of the kernel that’s become problematic.
Cgroup allows fine-grained resource partitioning among competing processes running on the same machine. It’s technically a kernel subsystem but it acts quite different than typical, more isolated subsystems such as drivers or architecture-specific systems like PCI or USB. Cgroup is a conduit for other subsystems to manage and query with kernel resources such as CPU time, amounts of memory, and groups of processes.