So you've heard of this thing called cgroups, and you are interested in finding out more. Perhaps you caught mention of it while listening to a talk about containerization. Maybe you were looking into Linux performance tuning, or perhaps you just happened to be traversing your file system one day and discovered /sys/fs/cgroups. Either way, you want to learn more about this functionality that has been baked into the kernel for quite some time. So sit back, grab some popcorn, and prepare to (hopefully) learn something you may not have known before.