Git Repository Cleanup & Large Object Reduction Report

🧠 Context

While maintaining a long-lived production repository, I noticed an unusually large .git/objects/pack file consuming hundreds of MBs.
This was affecting cloning speed, CI performance, and overall repository health.

🧪 Investigation

Checked .git folder size:
```
du -sh .git
```
Verified large pack files inside .git/objects/pack:
```
ls -lh .git/objects/pack
```

Analyzed top largest Git objects:

git verify-pack -v .git/objects/pack-xxxx.pack | sort -k3 -n | tail -20

Mapped object hashes to actual file paths:

git rev-list --objects --all | grep <hash>

⚙️ Cleanup Process

A Python automation script was created to:

Identify large Git objects (>10MB)
Map them to their actual file paths
Confirm user intent
Execute git filter-repo cleanup
Repack repository using git gc --aggressive
Measure before/after repo size

python analyze-pack.py --cleanup

When the repo had unstaged changes or wasn’t a fresh clone, the script smartly prompted for --force cleanup if safe.

🧩 Key Commands Used

git filter-repo --invert-paths --path <large-file-path>
git gc --prune=now --aggressive
git remote add origin <your-remote-url>
git push origin main --force

📦 Result

Initial size: 769.58 MB
Final size: ~220 MB
Reduction: 71% smaller! 🎯
History cleaned from large assets like .zip, .sql, .psd, .rar files.

💡 Lessons Learned

Always inspect .git/objects/pack when repo grows unexpectedly.
Use git filter-repo (not BFG) for safe & modern cleanup.
Never forget: after git filter-repo, your remotes are removed — re-add them manually!
Automating cleanup ensures consistent reproducibility in DevOps pipelines.

🧭 Takeaway for Teams

Regular repository hygiene saves:

Developer time (faster clone & fetch)
CI/CD cost (smaller artifacts)
Fewer headaches in the future 🚀

🧰 Recommended Tools

git filter-repo
du, grep, awk
pyenv + Python script automation

#GitOptimization #SoftwareEngineering #DevOps #CleanCode #PythonAutomation

4sskick/git_large_pack_cleanup_report.md