Tips for Building Lightweight Docker Images

Transcript

1. @kellyjandrews Tips for Building Lightweight Docker Images Kelly J Andrews - Developer Advocate, Codeship
2. @kellyjandrews Docker Images
3. @kellyjandrews Docker Images
4. @kellyjandrews Docker Images What is a docker image
5. @kellyjandrews Docker Images A Docker image is built up from a series of layers. Each layer represents an instruction in the image’s Dockerfile. Each layer except the very last one is read-only. Source: docker.com
6. @kellyjandrews Docker Images FROM ubuntu:15.04 COPY . /app RUN make /app CMD python /app/app.py
7. @kellyjandrews Docker Images Source: docker.com
8. @kellyjandrews Docker Images Source: docker.com
9. @kellyjandrews Smaller = Better
10. @kellyjandrews Smaller is Better Large Images = Longer Download Times Node Latest - 84 sec. Wheezy - 63 sec. Slim - 13 sec. Alpine - 12 sec.
11. @kellyjandrews Smaller is Better Large Images = More Disk Space Node Latest 667 MB Wheezy 522 MB Slim 226 MB Alpine 64.7 MB
12. @kellyjandrews Smaller is Better Large Images = Unused Programs Node Latest - 786 Wheezy - 719 Slim - 496 Alpine - 329
13. @kellyjandrews Docker Dieting Tips
14. @kellyjandrews Docker Dieting Tips Best Practices for Building Minimal Docker Images https://resources.codeship.com/ebooks
15. @kellyjandrews Docker Dieting Tips Use Fewer Layers RUN apt-get update -y RUN apt-get install -y curl RUN apt-get install -y postgresql RUN apt-get install -y postgresql-client
16. @kellyjandrews Docker Dieting Tips Use Fewer Layers RUN apt-get update -y && \ apt-get install -y curl postgresql postgresql-client
17. @kellyjandrews Docker Dieting Tips Clean Up After Yourself RUN apt-get update -y && \ apt-get install -y curl postgresql postgresql-client && \ rm -rf /var/lib/apt/lists/*
18. @kellyjandrews Docker Dieting Tips Base Images Node Latest 667 MB Wheezy 522 MB Slim 226 MB Alpine 64.7 MB
19. @kellyjandrews Docker Dieting Tips Optimize Dockerignore File root # ls mycode tmp logs $ echo “tmp” >> .dockerignore $ echo “logs” >> .dockerignore
20. @kellyjandrews Docker Dieting Tips Jessie Frazelle github.com/jessfraz/dockerfiles