I'm curious if anyone knows if the optimizations Twitter made to improve fetch performance for large, active repos have made it upstream yet? I don't work there

I'm curious if anyone knows if the optimizations Twitter made to improve fetch performance for large, active repos have made it upstream yet? I don't work there anymore and neither do any of the people who were originally doing that work, but it was a pretty impressive speed up (I could git pull thousands of commits and be done in under a second on a 3GB repo with no large objects). I know the watchman support made it in, which was the other half of what made large repos perform well, but I haven't seen mention of the log-structured patch queue stuff that helped the server by eliminating most of the work to calculate what to send on a fetch. Anyone know?