> In the example it seems pretty clear to me that: > Mutex::new(AppConfig::default()); > ...is meant to be acquiring a mutex protecting some global config

> In the example it seems pretty clear to me that: > Mutex::new(AppConfig::default()); > ...is meant to be acquiring a mutex protecting some global config object, yes? That's what I'm calling a "global lock". You could certainly have a global lock at the top-most level, but you're not required to. The example is just an example.