As far as I know, there is nothing fancy about it, except for the fact that a lot of work has been put into Go's garbage collector, especially in versions 1.5 and 1.6, with people working full-time on it.

Go easily achieves GC latencies well below 10 ms, even for programs using a large heap, without having to manually "tune" the GC.

https://blog.golang.org/go15gc

https://talks.golang.org/2015/go-gc.pdf

Go 1.5 concurrent garbage collector pacing, https://docs.google.com/document/d/1wmjrocXIWTr1JxU-3EQBI6BK...