GVFS(Git Virtual File System) from Microsoft

Microsoft announcement about a new file system and surprise, they open sourced it.

Here at Microsoft we have teams of all shapes and sizes, and many of them are already using Git or are moving that way. For the most part, the Git client and Team Services Git repos work great for them. However, we also have a handful of teams with repos of unusual size! For example, the Windows codebase has over 3.5 million files and is over 270 GB in size. The Git client was never designed to work with repos with that many files or that much content. You can see that in action when you run “git checkout” and it takes up to 3 hours, or even a simple “git status” takes almost 10 minutes to run. That’s assuming you can get past the “git clone”, which takes 12+ hours.

It seems to be a trend with these big companies. Similar steps has been done by Facebook but on Mercurial though. Google also uses a single repository but there is not much information about the implementation from Google though.