Then the kernel runs an 'initialization' process, which is launchd on your Mac. The kernel is the core glue between the hardware and the operating system. When your computer boots, it loads the 'kernel' program into memory and hands over control to it. Look at the top of the process tree, and you'll see that every process on your Mac is a child of two parent processes:Īll operating systems have a ' kernel', the core computer program of the operating system that controls everything and facilitates access to hardware. In the htop process viewer interface, press t to switch to tree view. Once the install completes, run it by typing htop and hitting enter. On your Mac, open a terminal and run brew install htop. Let's install the process viewing application htop to get an understanding of how containers work. Just replace Homebrew with your package manager. These instructions are tailed for MacOS users, but work for Linux users as well. Why, then, do Docker 'image' files start with lines like FROM ubuntu? Are containers running full Ubuntu operating systems? If not, why do we specify an entire operating system? For that matter, what does it even mean to 'run an operating system? In Docker, we run processes in isolated environments, such as Rails applications or Node.js applications. All posts tech nutrition growth Here's Why Docker Images Start With 'FROM ubuntu'

Ubuntu container with docker on mac