Optimize Local Git Repository by Running Garbage Collection

Over time, the local Git repository can accumulate unnecessary files and metadata, leading to increased disk space usage and potentially slower performance. Git provides a built-in mechanism to clean up and optimize the repository: garbage collection (GC). This tutorial explains how to optimize local Git repository by running garbage collection.

Git automatically performs garbage collection under specific conditions to prevent excessive disk usage and maintain optimal performance. This process is triggered by commands such as git commit, git merge, and git rebase.

It is also possible to run garbage collection manually by using command:

git gc

If you want a deeper cleanup and better compression, use --aggressive option:

git gc --aggressive

The --aggressive option performs a more comprehensive and in-depth cleanup than the default execution. This takes more time and cost of more CPU usage, but can significantly reduce repository size and improve efficiency.

Manually running garbage collection can be especially beneficial in several scenarios:

• Pre-backup repository cleanup - before creating a backup, running garbage collection ensures that the repository is compact, well-organized, and free of unnecessary data.
• Post-ref deletion cleanup - if you've recently removed numerous branches, tags, or other references, garbage collection helps eliminate unneeded objects and metadata, keeping the repository optimized.