use_current_thread and the global thread pool about rayon HOT 2 CLOSED

rayon::scope runs its closure within the pool -- this is its main distinction versus in_place_scope. Your playground even shows this by ThreadId numbers, where main is 1 and the pool (including the scope) run on 2 and 3. Your main thread is entirely blocked until it all finishes.

https://docs.rs/rayon/latest/rayon/fn.scope.html

The closure given to scope() executes in the Rayon thread-pool, as do those given to spawn().

https://docs.rs/rayon/latest/rayon/fn.in_place_scope.html

This is just like scope() except the closure runs on the same thread that calls in_place_scope(). Only work that it spawns runs in the thread pool.

from rayon.

You are right, I must have misread the output from the playground. Confirmation bias, I guess. I missed the part about the closure being run in the thread pool and thought it would be like std's.

from rayon.