The Linux Kernel: Top 5 Innovations
The word innovation gets bandied about in the tech industry almost as much as revolution, so it can be difficult to differentiate hyperbole from something that’s actually exciting. The Linux kernel has been called innovative, but then again it’s also been called the biggest hack in modern computing, a monolith in a micro world. Setting aside marketing and modeling, Linux is arguably the most popular kernel of the open source world, and it’s introduced some real game-changers over its nearly 30-year life span.
Back in 2007, Paul Menage and Rohit Seth got the esoteric control groups (cgroups) feature added to the kernel (the current implementation of cgroups is a rewrite by Tejun Heo.) This new technology was initially used as a way to ensure, essentially, quality of service for a specific set of tasks. For example, you could create a control group definition (cgroup) for all tasks associated with your web server, another cgroup for routine backups, and yet another for general operating system requirements.
You could then control a percentage of resources for each cgroup, such that your OS and web server gets the bulk of system resources while your backup processes have access to whatever is left. What cgroups has become most famous for, though, is its role as the technology driving the cloud today: containers. In fact, cgroups were originally named process containers.
It was no great surprise when they were adopted by projects like LXC, CoreOS, and Docker.