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Comment by fulafel | Hacker News Reader

The secret to the lightweight nature of Docker is that it just uses various namespacing, cgroup etc functionality provided by Linux with no virtualized OS kernel or hw virtualization mechanisms involved.

(Yep you need ARM Docker images when running on ARM of course)

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It does on linux. On macOS and windows it does still do this... but in a linux VM.

Yep. Linux gaining HW support for the M1, and Docker on your penguinized mac, was the context I thought.

Do we really expect to see many Docker images published that are compiled for ARM? Sure, I expect to see base OS images, but I'd find it hard to believe that many people are going to take the time to cross-build and publish an arm64 version of their container image alongside their x86_64 version.

I guess to some extent that might be generally useful, what with things like AWS's Graviton ARM processors, but I expect it'll take a while.

Most people build their own images using CI/CD to their own registries when using containers in production [1]. You don't really otherwise know what is in them. And for on-laptop hacking it's just a docker build command.

[1]Especially now that public docker hub is ip rate limited to uselessness.

Anecdotally, we already do see a substantial number. Far from 100%, but many of the most popular images on Docker Hub are already multi-arch. The most notable exception is the Docker-maintained MySQL image, but Oracle maintains another which works fine on ARM.

Wouldn't Docker still need a VM for Linux containers on any non-Linux OS? My understanding is that it uses the host's kernel, so running it on macOS would always require a VM.

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