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by raesene2 3192 days ago
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/
2 comments
jbergstroem 3192 days ago
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...

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e12e 3192 days ago
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?
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nathan-osman 3191 days ago
The entirety of Debian 0.97 (kernel, userspace, packages) fit on two floppies back in 1994 :P
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jbergstroem 3191 days ago
For that I reckon you'd have to file a bug with golang.
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nathan-osman 3192 days ago
Yes, I use Alpine for a lot of my other containers. I love the simplicity of the package manager as well.
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theptip 3192 days ago
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.
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colemickens 3192 days ago
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.
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jbergstroem 3192 days ago
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...
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freedomben 3191 days ago
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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