How to Fix Git Repository Issues After Accidentally Committing Large Files

If you’ve accidentally committed a large file (like a JAR, ZIP, or binary file) to your Git repository, you might run into issues when trying to sync with remote repositories like GitHub, GitLab, or Bitbucket. Large files can bloat your repository, exceed size limits, and cause errors during pushes or pulls. In this guide, we’ll walk you through how to troubleshoot and fix this issue step by step.

Why Large Files Cause Problems in Git

Git is designed to handle text-based source code efficiently, not large binary files. When you commit a large file:

• Repository Size Increases: The file is stored in Git’s history, even if you delete it later.
• Push/Pull Fails: Remote repositories often have size limits (e.g., GitHub’s 100 MB file limit).
• Performance Degrades: Cloning, fetching, and pushing become slower.

To fix this, you need to remove the large file from your Git history and clean up your repository.

Step 1: Identify the Large File

First, identify the large file(s) causing the issue. You can use the following command to list the largest files in your repository:

git rev-list --objects --all | grep $(git verify-pack -v .git/objects/pack/pack-*.idx | sort -k 3 -n | tail -10 | awk '{print$1}')

This command lists the 10 largest files in your repository. Note the file path(s) for the next steps.

Step 2: Remove the Large File from Git History

Manually deleting the file from your working directory isn’t enough—it still exists in Git’s history. To completely remove it, you need to rewrite your Git history.

Option 1: Use git filter-repo (Recommended)

git filter-repo is a modern, fast tool for rewriting Git history.

1. Install git filter-repo:

   pip install git-filter-repo

2. Remove the large file: Replace path/to/large-file.jar with the path to your file.

   git filter-repo --path path/to/large-file.jar --invert-paths

3. Force push the changes:

   git push origin --force --all
   git push origin --force --tags

Option 2: Use git filter-branch (Older Method)

If you don’t have git filter-repo, you can use git filter-branch:

1. Run git filter-branch: Replace path/to/large-file.jar with the path to your file.

   git filter-branch --force --index-filter \
   'git rm --cached --ignore-unmatch path/to/large-file.jar' \
   --prune-empty --tag-name-filter cat -- --all

2. Force push the changes:

   git push origin --force --all
   git push origin --force --tags

Step 3: Clean Up Your Repository

After removing the large file, clean up your repository to free up space:

1. Run garbage collection:

   git reflog expire --expire=now --all
   git gc --prune=now --aggressive

2. Verify the file is removed: Check your Git history to ensure the file is gone:

   git log --all -- path/to/large-file.jar

Step 4: Prevent Future Issues

To avoid accidentally committing large files in the future:

• Use .gitignore: Add file patterns for large files (e.g., *.jar, *.zip) to your .gitignore file:

  echo "*.jar" >> .gitignore
  git add .gitignore
  git commit -m "Ignore JAR files"

• Use Git LFS (Large File Storage): Git LFS stores large files outside your repository, keeping your history lightweight.
  1. Install Git LFS:

     git lfs install

  2. Track large files:

     git lfs track "*.jar"
     git add .gitattributes
     git commit -m "Track JAR files with Git LFS"

• Pre-Commit Hooks: Use pre-commit hooks to check for large files before committing.

Step 5: Rebase or Squash Commits (If Needed)

If you’ve made additional commits after adding the large file, rebase or squash them to ensure they don’t reference the file:

1. Interactive rebase:

   git rebase -i HEAD~5

   Replace 5 with the number of commits you want to review.
2. Force push the changes:

   git push origin --force

Accidentally committing large files to a Git repository can cause significant issues, but with the right tools and techniques, you can clean up your repository and prevent future problems. By using tools like git filter-repo, Git LFS, and .gitignore, you can keep your repository lean and efficient. If you’re still having trouble, feel free to reach out in the comments below or consult your Git hosting provider’s documentation for additional support.