Cgroups, namespaces, and beyond: what are containers made from?
Why Hacker News recommends it
HN recommends it as a talk that makes containers click, showing that containerization is not virtualization and demystifying what Docker does.
What it is
Jérôme Petazzoni explains how Linux containers are built from kernel features like cgroups, namespaces and SELinux. He demonstrates putting the pieces together by hand to make a container and compares runtimes and approaches like jails and zones.
Recommended by 4 HN commenters across 3 different months, 2017 to 2023.
What Hacker News said
Strong rec dominotw · 2017-12 · on “Demystifying container runtimes”
I watched this talk couple of years ago that made docker/containers finally click for me. Cgroups, namespaces, and beyond: what are containers made from? - Jérôme Petazzoni, [this video]
Strong rec dmpanch · 2023-06 · on “Build Your Own Docker with Linux Namespaces, Cgroups, and Chroot”
This topic is perfectly covered in a presentation by Jérôme Petazzoni from Dockercon 2015, a Docker developer, on how containerization works. After watching the video, I began to clearly understand that this is not virtualization at all, as many at first imagine. [this video]
Recommends antoncohen · 2017-12 · on “Ask HN: Good resources on learning how docker works under the hood?”
Jérôme Petazzoni's talk on cgroups, namespaces, etc. I think he has given the talk a bunch of times, I saw it in person once, here is a video I found: [this video] He goes into cgroups, namespaces, etc. Then does a demo where is manually does what docker does, like untars an image, creates namespaces, creates the networking.
Recommends hardwaresofton · 2018-04 · on “A Workshop on Linux Containers: Rebuild Docker from Scratch”
In the same vein: Building a container from scratch in Go (Liz Rice) @ Container Camp 2016 -> [LINK] What's a container really let's write one in go from sctach (Liz Rice) @ Golang UK Conference -> [LINK] Cgroups, Namespaces and beyond: What are containers made from (Jerome Petazzoni) @ DockerCon 2015 - [this video] Building Containers in Pure Bash and C (Jessica Frazelle) @ ContainerSummit 2016: [LINK] First two are basically the same talk, but it doesn't hurt to hear the same ideas more than once.
Cites Bayart · 2022-01 · on “We're migrating many of our servers from Linux to FreeBSD”
>There is controversy about Docker not running on FreeBSD but I believe (like many others) that FreeBSD has a more powerful tool. Jails are older and more mature - and by far - than any containerization solution on Linux. If FreeBSD jails and Solaris zones were equivalent to Linux containers, we'd have seen them take over the backend already. We haven't. They're really useful, they provided a degree of safety and peace of mind for multi-tenancy but they're not granular enough for what's done with $CONTAINER_RUNTIME these days. Jérôme Petazzoni has an old talk where he touches upon container primitives and compared them to jails : [this video]