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by deeviant 4259 days ago
Is minimizing the size of a docker image really the top priority?

I would hold that making docker images easy to use, transparent as possible, reliable, versatile and easy to use (did I mention that already? oops) are far more important priorities.

Admittedly, I use docker primarily for development/testing purposes and my use-cases are a bit different than the average production use-case, however, having a large toolbox easily accessible for me to use (yes, including the ability to ssh into the docker container) is invaluable to me.

I may be missing something here, but racing to make docker images "as small as possible" feels like a bit of premature optimisation.
5 comments
samcday 4258 days ago
If we were talking about shaving a couple of bytes off a layer, I'd agree that attention might be better focused elsewhere.

However, I've seen (and am guilty of) a few of the pitfalls in the parent post. When you suddenly start adding 100mb+ unnecessarily to a Docker image, it can have some nasty ramifications in devspeed, and also deployments. A classic way to accidentally dramatically increase the weight of a Docker image is to apt-get install build-essential.

What kinds of ramifications you might ask? Well, I live in Australia. I don't know if Docker Registry has a CDN POP here, but that extra 100mb tends to take a solid minute or two longer for me to pull down.

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jpgvm 4258 days ago
It's not a question of size but a question of semantics.

If you dump an OS in a container you are treating it like a lightweight VM (and that might be fine in some/many cases).

If however you restrict it to exactly what you need and it's runtime dependencies + absolutely nothing more then suddenly it's something else entirely - it's process isolation, better yet it's -portable- process isolation.

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simi_ 4258 days ago
+1

If it doesn't hinder runtime performace +/- 100MB of disk space is fairly benign. I understand how smaller images would be useful, but for my use case it doesn't help much.

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justincormack 4258 days ago
If you are making services small and having lots of them and redeploying often it matters more. If you just have one at a time maybe you dont care.
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jaequery 4258 days ago
yes, exactly how i feel too.
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