I have created a couple different directories on my host machine as I try to learn about Docker just to keep my dockerfiles organized. My Dockerfile I just ran looks like this:
FROM crystal/centos
MAINTAINER crystal
ADD ./rpms/test.rpm ./rpms/
RUN yum -y --nogpgcheck localinstall /rpms/test.rpm
My actual rpm is only 1 GB. But when I try to do sudo docker build -t="crystal/test" .
, I get sending build context to Docker daemon 3.5 GB. Is there something else that I'm unaware of as you continue to build Docker images? Is my memory accumulating as I build more images in my other directories on my host machine?
The Docker client sends the entire "build context" to the Docker daemon. That build context (by default) is the entire directory the Dockerfile
is in (so, the entire rpms
tree).
You can setup a .dockerignore
file to get Docker to ignore some files. You might want to experiment with it.
Alternatively, you can move your rpms
folder one directory level above your Dockerfile
, and only symlink test.rpm
into the Dockerfile
's directory.
You’ll often want to add the .git
folder to the .dockerignore
which was the cause of a 150MB -> 5GB difference for some users in the comments here.