Контроль ресурсов в списке "зачем людям Docker" если и есть, то месте на последнем примерно.Вот взгляд типичного Docker-пользователя:
>In order to better understand Docker you have to understand the problem it is trying to solve.
>Modern day development (I’ll be focusing on the web here) lives in a world of lots of complexity. In even the most basic application you are likely to have a back-end language that lives on the server, a front-end language (almost ubiquitously JavaScript) that lives on the client, third-party and in-house libraries for both of these languages to manage, a database, an operating system (often deploying to Linux but developing on God-knows-what OS), and more. And this is for a basic app! What if you have utility programs that are written in another language? What if you have other weird dependencies and requirements?
>My point is that this all adds up to a lot of complexity, and worst of all- it is complexity that you have to manage across multiple platforms. If I got an app up and running on my Macbook, and wanted to deploy to Linux, my options were not great. If you’ve ever administrated your own VPS, much less a bare metal server, you know what I mean. Having to install all of the packages and dependencies that you have in a totally different way is a recipe for headaches and tears. Getting stuff to production is a completely different ball game from writing it in the first place. Different technologies on different platforms create a “Matrix from Hell” (pictured above) that makes even the most courageous ops person want to set her hair on fire.
>Traditionally there have been a variety of solutions that have popped up in response to this, ranging from “just develop in PHP and FTP is your deploy” (ew) to Heroku (git push heroku master is your deploy) to virtualization with provisioning (see Vagrant). Vagrant in particular has been gaining a lot of steam lately, for very good reason, and is a great technology (see my post on how we won Startup Weekend if you’re curious why Vagrant was useful to us in that case). However, virtual machines have several disadvantages as well. Because the VM software has to simulate actual physical hardware, you take a big performance hit. They are slow to start up and, especially before Vagrant started to become popular, difficult to get inexperienced developers started on (Download Vagrant and its dependencies and run vagrant up is a lot nicer than going through all of the VirtualBox menus, then provisioning your box manually).
