That is not an argument against releasing the code. Why would Google assign itself as gatekeeper? I personally could use this code on supercomputers now. I don't work for a supercomputing company; my use case is academic work and computational science. I absolutely have thousands of huge machines that I multiplex trusted binaries to -- and scheduling is not a trivial problem.
So what's the real reason nobody gets to see this code?
The code is literally millions of LoC, all of which needs to be audited for stuff we can't release for whatever reasons. All that code is built upon layer after layer of Google internal stuff. Open-sourcing Borg means open-sourcing Chubby, internal form of gRPC (older), hundreds of libs, monitoring infrastructure, etc. Net result is O(50M) LoC. And when someone sends us a patch - then what? The cost of doing it is simply prohibitive. I'd love to do it, it's just not practical and has no RoI.
That's a much more sensible reason! If the code is truly Google specific, then I agre. It sounded to me like the code was not released because nobody else has a lot of computers, which I found odd.
So what's the real reason nobody gets to see this code?