Microsoft Is Now Using Linus Torvalds' Open Source Tool For Windows Development

I saw this a few days ago from other sources. Here's some from last week:
https://blogs.msdn.microsoft.com/bharry/2017/05/24/the-largest-git-repo-on-the-planet/
https://arstechnica.com/information-technology/2017/05/90-of-windows-devs-now-using-git-creating-1760-windows-builds-per-day/

The really fascinating part is not that it's Git, but the changes they've made to Git to enable it to work: in particular, the Git Virtual File System (GVFS), so that people don't have to set up 300GB of data at first run, and the change tracking improvements to fix Git's tendency to unnecessarily "touch" files as part of comparison operations. Those are big, noteworthy changes that I believe will get wider adoption.

Microsoft has always had a tendency for different groups to do different things. There were teams using Microsoft's own (horrible) SourceSafe all the way until circa 2011. Git was already in use by some teams for at least few years already. Even after this move, some groups will still use TFS (also MS developed, but not junk like SourceSafe), others will continue to use Source Depot (what Git is mostly replacing), and I wouldn't be surprised if Subversion and Mercurial still make an appearance from time to time.

Also interesting is the comparison to Amazon's repo, which they custom-built and call Piper, which holds an estimated 86TB of data.
https://cacm.acm.org/magazines/2016/7/204032-why-google-stores-billions-of-lines-of-code-in-a-single-repository/fulltext

Microsoft had to fix GitHub so that it could handle the hyper-scale of Microsoft.