Fix: GitHub Actions Runner Disk Full During Build

!Symptoms

• Build fails with 'No space left on device'
• Docker build step fails during large layer creation
• npm/pip install fails writing to disk
• Artifact upload fails due to insufficient space

?Root Causes

• GitHub-hosted runners have limited disk space (~14GB free)
• Docker images and layers consuming space from previous steps
• Large build artifacts or dependencies filling the disk
• Multiple Docker builds without intermediate cleanup
• Node modules or Python virtualenvs consuming excessive space

#Diagnosis Steps

1. 1Add `df -h` step before the failing step to see disk usage
2. 2Check Docker space: add `docker system df` step
3. 3Check which directory is largest: `du -sh /home/runner/work/*`
4. 4Review previous steps for large downloads or builds
5. 5Check if caching is storing too much data

>Fix

1. 1Free space by removing unused software: `sudo rm -rf /usr/share/dotnet /usr/local/lib/android /opt/ghc`
2. 2Clean Docker between steps: `docker system prune -af`
3. 3Use `actions/cache` with proper key rotation to avoid stale caches
4. 4Split the workflow into multiple jobs that run on fresh runners
5. 5Use multi-stage Docker builds to reduce layer sizes

*Prevention

• Add a disk space check step at the start of workflows
• Use larger runners (GitHub-hosted or self-hosted) for big builds
• Implement Docker layer caching with `docker/build-push-action`
• Clean up intermediate artifacts between build steps
• Use .dockerignore and .npmrc to minimize what gets copied/installed

Related Error Messages