How to optimize Docker image size? #45
Description
Hi, i was finally able to build a Docker image with Bistro, but i am a bit worried about it's enormous size. It has roughly 5.2gb.
Do you have any tips how to reduce it's size?
It is automatically generated Dockerfile using fbcode_builder.
Basically it is repeating blocks of download+build+install blocks:
### Check out fmtlib/fmt, workdir build ###
USER root
RUN mkdir -p '/home' && chown 'nobody' '/home'
USER 'nobody'
WORKDIR '/home'
RUN git clone https://github.com/'fmtlib/fmt'
USER root
RUN mkdir -p '/home'/'fmt'/'build' && chown 'nobody' '/home'/'fmt'/'build'
USER 'nobody'
WORKDIR '/home'/'fmt'/'build'
RUN git checkout '6.2.1'
### Build and install fmtlib/fmt ###
RUN CXXFLAGS="$CXXFLAGS -fPIC -isystem "'/home/install'"/include" CFLAGS="$CFLAGS -fPIC -isystem "'/home/install'"/include" cmake -D'CMAKE_INSTALL_PREFIX'='/home/install' -D'BUILD_SHARED_LIBS'='ON' '..'
RUN make -j '4' VERBOSE=1
RUN make install VERBOSE=1
I was thinking if i can somehow remove cache. Maybe just rm -rf /fmt (same for every other cloned repository) after package is installed could help to reduce size.
As well i do not usually use c++ so i do not know how it really works internally, please if i am mistaken and my idea is stupid, just correct me 😄 if we could take only the final binaries and extract them to different, clean, docker image?
Other idea was using some alpine based linux or other base image than ubuntu (quick googling brought me to https://github.com/madduci/docker-cpp-env).
Can anything of this work or would you suggest anything completely different?
I was thinking about having autoscaling mechanism for bistro workers etc on aws spot instances (maybe even as lambdas) and for these purposes i wanted to have image as thin as possible.