Slim down your git repository size¶

20 June 2016 by Anil

Tutorial

Table of Contents

Removing the files from your existing git repository
- Pruning the repository

I’ve recently moved to Github for my private repositories and was in the process of migrating my repositories over. I wanted to be a good citizen and reduce my repository size as much as possible by excluding binaries I had previously committed on an iOS project.

Here’s how I did it.

Removing the files from your existing git repository ¶

First, we’ll need to add our large files to our .gitignore and tell git to stop tracking them.

In my case, I ignored these frameworks from an iOS project I’m working on, I can easily re-install them using package manager CocoaPods.

# .gitignore
Pods/Realm
Pods/Crashlytics
Pods/Fabric
Pods/TwitterKit
Pods/Digits
Pods/TwitterCore

We’ll need to tell git to stop tracking these files.

git rm -r --cached Pods/Realm
git rm -r --cached Pods/Crashlytics
git rm -r --cached Pods/Fabric
git rm -r --cached Pods/TwitterKit
git rm -r --cached Pods/Digits
git rm -r --cached Pods/TwitterCore

You’ll have to commit and push your changes.

Remember to add your updated .gitignore.

# Your removed cached items should be automatically added
git add .gitignore
git commit -m "Removed large files for prune"
git push origin master

Pruning the repository ¶

We’ll use a popular tool called bfg which removes large files like git-filter-branch does.

Installing bfg ¶

Install it via homebrew (or your preferred means) like so:

brew install bfg

Prepare the repository ¶

Create a bare clone of your git repository:

git clone --mirror git@github.com:lakhman/fat-repo.git

Note

Note This will clone your actual core repository history, and so you will not see your files here.

Create a backup of the repository:

cp -r fat-repo.git fat-repo.git-backup

Remove the files from your local repository ¶

Remove all files larger than 1M.

bfg -b 1M fat-repo.git

This will remove all files over 1000K, except HEAD (which is protected). View all the options by reading the docs or running bfg.

The bfg command should output a command like so, you need to run this in your project root to finalize the process.

# Jump into our project
cd fat-repo.git

# reflog - Process our reference logs as we've manually updated them
# gc     - Cleanup unnecessary files and optimize the local repository
git reflog expire --expire=now --all && git gc --prune=now --aggressive

You can view more information about these commands here:

gc	https://git-scm.com/docs/git-gc
reflog	https://git-scm.com/docs/git-reflog

Push your changes to your remote ¶

Finally, we’ll want to push our changes to a remote repository.

Tip

Use git config --list to view your settings.

It’s best to do this in a new repository, create one (I’ll be using Github, we’ll call it slim-repo).

git remote remove origin
git remote add origin git@github.com:lakhman/slim-repo.git
git push -u origin master

If you’re using Github, you can see your repository size by going to your Account Settings > Repositories.

You should now have a slimmer repository, remember you’ll have to clone your repository again as the references will have changed during this the process.