How to reduce the image size of dockers?

Question

I am using docker official rails onbuild pack ( https://registry.hub.docker.com/_/rails/ ) to create and create a relay image using the application. But each application takes about 900 MB. Is it possible to reduce this size?

Here is my workflow →

add dockerfile to the project -> build -> run

The problem is that in this system there can be N number of applications, and if each application takes 1G of disk space, this will be a problem. If we reduce the layers, will it reduce the size? If so, how can this be done?

REPOSITORY           TAG                 IMAGE ID            CREATED              VIRTUAL SIZE
blog2                latest              9d37aaaa3beb        About a minute ago   931.1 MB
my-rails-app         latest              9904zzzzc2af        About an hour ago    931.1 MB

Answer 1

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