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Comment by raesene2 | Hacker News Reader

If you base off alpine, you can get useful containers quite a lot smaller than 100MB.

One example i use is an agent i deploy to kubernetes clusters to do some security scanning. The scripts are ruby and the image clocks in at 9MB compressed https://hub.docker.com/r/raesene/kaa-agent/tags/

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On the same note I did a mariadb container that is ~12mb: https://hub.docker.com/r/jbergstroem/mariadb-alpine/

If you're into go, it's not too hard to get very small (<5mb) shippables by statically compiling against musl and using upx. Here's a somewhat scrubbed Dockerfile for a gRPC/rest service I use at work: https://gist.github.com/jbergstroem/680cb7db6f90319dcd7666f3...

5mb still sounds like a lot, considering you could squeeze Linux 1.3 on a 1.44 mb floppy with a (compressed) rootfs... I mean does the runtime really do that much more than a full (although old) os kernel and a C library/runtime and apps?

The entirety of Debian 0.97 (kernel, userspace, packages) fit on two floppies back in 1994 :P

For that I reckon you'd have to file a bug with golang.

Yes, I use Alpine for a lot of my other containers. I love the simplicity of the package manager as well.

Alpine's package manager has the great property that you don't need to update the index in order to fetch a package IIRC; the whole `apt-get update && apt-get install && <cleanup apt-cache>` dance is quite tedious in debian-based Docker containers.

No, you still need to, but there's a compact syntax for it that will update and discard the index in a single 'add' command. It's unavoidable - somewhere some querying is happening in order map the package name/ver to a download link.

I find the haproxy (alpine) Dockerfile a great example on how to tender to container file-size. It uses the syntax you're referring to, temporary build virtuals (should be multistage today I guess) and static linking: https://github.com/docker-library/haproxy/blob/2d393f2b59824...

Awesome example, thanks. We've been starting using different Dockerfiles for prod and dev. For prod we want tiny images, but for dev the caching of layers is more important for frequent rebuilds. Such balance all the time :sigh:

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