Docker इमेजेस ऑप्टिमाइज करणे म्हणजे साइज कमी करणे (लहान, वेगवान, अधिक सुरक्षित) आणि बिल्ड परफॉर्मन्स सुधारणे (कॅशिंगद्वारे वेगवान बिल्ड्स). तंत्रांमध्ये न्यूनतम बेस इमेजेस, मल्टी-स्टेज बिल्ड्स, लेयर ऑप्टिमाइজेशन, BuildKit, आणि सावधान Dockerfile डिজाइन समाविष्ट आहे.
इमेज साइज कमी करणे
✓ MINIMAL base images:
- alpine (tiny, ~5MB) — but musl libc can cause compatibility issues for some apps
- slim variants (e.g. python:3.12-slim) — smaller than full, fewer compat issues
- DISTROLESS — only the app + runtime, NO shell/package manager (smallest, most secure)
- scratch — empty base (for static binaries, e.g. Go) → minimal image
✓ MULTI-STAGE builds — build with tools, ship only the artifact (huge size savings)
✓ Combine RUN layers + clean up IN the same layer:
RUN apt-get update && apt-get install -y x && rm -rf /var/lib/apt/lists/*
(cleanup in a SEPARATE layer doesn't shrink the image — the files are in the earlier layer)
✓ .dockerignore — keep junk out of the context/image
✓ Remove caches, temp files, dev dependencies in production images
