The reason Google developed Piper was basically that Perforce couldn't scale beyond a single machine, and our repo was getting too large to even be usable on th

The reason Google developed Piper was basically that Perforce couldn't scale beyond a single machine, and our repo was getting too large to even be usable on the biggest, beefiest x86 server that money could buy (single machines with terabytes of ram and zillions of cores). If Microsoft has close to the same amount of code in a single repository, then they must have also written their own version control service that runs on more than one machine. The last rumors I heard is that Microsoft bought a license to the Perforce source code, and created their own flavor to host internal code ("Source Depot" ?), which presumably still runs on a single machine.