[MichaelMoser123]

Thanks for the link, it is explained in the linked video:

https://www.youtube.com/watch?v=KXuZi9aeGTw They explain it around 15:01 - google added it's own syscall switchto_thread - that puts the current thread to sleep and is switching to the argument thread id. (and some other calls too). That one helps with cutting down latency in inter thread calls for m:n threading. The real effort is to make latency for individual application requests predictable, while keeping it low.