Reduce layer size

[Leguan16]

When trying to push my image that uses this one as a base i encountered issues that the layer where it runs instal-packages.sh is too big.

This change reduces the layer size enough to make that possible again.

[itzg]

Thanks. I'm curious: how much was too big for an image layer size?

[Leguan16]

Since we proxy our registry through cloudflare the limit is either 100 or 200mb and the layer had 220mb.

Now I am not too sure if my observation was correct and encourage own testing but when i tried to push our image with my fix the biggest layer was 60mb. (took the most time to push).

[Leguan16]

Additionally, according to the Docker Documentation official Debian and Ubuntu images already run apt-get clean automatically.

[itzg]

Since we proxy our registry through cloudflare the limit is either 100 or 200mb and the layer had 220mb.

Now I am not too sure if my observation was correct and encourage own testing but when i tried to push our image with my fix the biggest layer was 60mb. (took the most time to push).

In my testing went from 267MB to 206MB after your change.

Testing with another image, it seems to be a constant reduction of 60MB regardless of how many packages were installed. So must be removing the remote repo indexes and apt-get clean was already removing the package caches.

[Leguan16]

Yeah i just saw it in the Docker Desktop dashboard that it went from 865mb to 814mb. -170mb sounded off anyway. Maybe that was the compressed size or something 😆