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From YouTube: Lightning Talk: What Made Your Container Fat? Visualizing the Size of Container Layers - Dan Čermák

Description

Don’t miss out! Join us at our upcoming hybrid event: KubeCon + CloudNativeCon North America 2022 from October 24-28 in Detroit (and online!). Learn more at https://kubecon.io. The conference features presentations from developers and end users of Kubernetes, Prometheus, Envoy, and all of the other CNCF-hosted projects.

Lightning Talk: What Made Your Container Fat? Visualizing the Size of Container Layers - Dan Čermák, SUSE

The analysis of container images is becoming increasingly important to deliver a high quality product. We have found it rather challenging to continously monitor the size of our container images that we were producing and existing tools were not focused on data visualization, which we wanted initially. The presented tool was born out of this necessity: it has a very simple user interface, requires no installation (it can be hosted on a server somewhere else) and features sunburst graphs showing the file system usage. This allows everyone to easily check which layer is where responsible for the overall image's size.

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Hi thanks everyone, so thanks for making it in such a numerous numbers to my lightning talk, what made your container fat so few words first about me: I'm a software developer working at susa part of the developer engagement program.

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I also do other stuff, mostly in developer tools, testing, I'm also a member of the fedora community, and in case you are not totally bored after this talk. You can also stalk me on some social media. Where I occasionally write, maybe interesting stuff. You can be the judge of that, but let's get to the actual topic at hand. So we at souza, we do all kinds of stuff and one of them is building containers and if you start building containers, you occasionally run into the issue.

A

Well, gosh the image got bigger, oh well, where and then you start unpacking container images and you start analyzing them and it starts to get confusing pretty pretty easily pretty fast, so where's, actually the size increase coming from.

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So maybe you want to take a closer look. Then you figure out. Okay, I have a big container image and got 20 layers which layer is now the actual culprit where, where the, where did it get the big and there? You can't really go into the old trick that you just launched the container image you install ncdu and you take a look because then you have to find the actual the actual layer.

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So you can unpack it and you put it somewhere in your temper temperfest and you get super and after you've done it 50 times, you have a huge temporary directory with all kinds of layers extracted and you forgot, which one is the actual one that you are looking for.

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So um then, so that's, unfortunately, a pretty cool tool for that it's called dive.

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But maybe you like prettier graphs and I like the gnome disk usage analyzer, which produces pretty nice sunburst charts, and I wanted something like that for container images as well and also what would be really nice being able to compare images side by side. And since I didn't see something for that, I wrote something. So let me let me show you this tool that essentially shows you a sunburst graph of a container layer.

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So if you want to see what actually is big in your container image on the file system, you can do it with that. So, let's jump into a short demo. What the how the tool looks like this is a real it's just a web app, so you can open it in your web browser. You give it a container image. It will show you the various platforms by which you can pull it, so you can select any architecture that you'd, like you, tell it to anna to pull it down in this in this short demo.

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It's I already had it pre-fetched so that we don't have to wait for five minutes, because my internet connection sucks, um then it will start analyzing it you'll get a you'll, get a pic you'll get a table of all the layers that are there and then you can plot them. You'll get a nice sunburst graph, you can click on them. It will zoom in the over you'll, see as one of the overlays is how how big the actual file is or the folder, and you can select another layer and yeah.

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Essentially it will give you all the all the interesting uh all the interesting information per layer.

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Okay, so that should be that one and now then then we then I thought well, okay! So now I can see what each layer looks like, but now I've now my image evolves over time and so well something changed. What so for that uh it neck cow, can do image compara. It can do comparison of various layers and will essentially show you the same picture just side by side. You give it two layers and everything. That's red means it's bigger. Everything, that's green means.

A

It's it's smaller yellow means it's the same and blue which uh well, let's just run the demo. So if you just click on any of that it will, it will show you the same folder in the corresponding image and if you take a look at, uh if you at some point see something yeah, there should have been a blue one as well. That means it's just present in this image. So since I'm running out of time, let's just take a look at a few of the features that are in there, so you can take.

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You can take container images from a registry or from a local archive, so you don't have to even push it anywhere.

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You can analyze images from various architectures, so you're not limited to your current systems, architecture, which also became crucial at some point.

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You can store them in a in a database. Currently that's sql light. It runs root list by default. If you like that, and if you want, you can run it on your local system as a containerized web app. So and if you don't want to type those commands, you can also just give it a try yourself and with that I'd like to thank you for your attention.