How is the file size at Overview > Details calculated?

Hi everybody!

I had to rewrite the history of a Git repo and I tried to replace the old repo with:

git push --mirror myURI

Now, the Overview > Details page shows a size under Files(xxx MB) that is 5 times as high as the actual repo size. How is this size calculated?

Housekeeping has not helped and removing the whole project and pushing to a new one is not an option either, because I’ve created a bunch of issues in the project.

Btw, I am using Gitlab CE and am really happy with it!