ARMANRIAZIRUSTRCVSARC
Unlike [Rc<T>], Arc<T> uses atomic operations for its reference counting. This means that it is thread-safe. The disadvantage is that atomic operations are more expensive than ordinary memory accesses.
If you are not sharing reference-counted allocations between threads, consider using [Rc<T>] for lower overhead.
[Rc<T>] is a safe default, because the compiler will catch any attempt to send an [Rc<T>] between threads. However, a library might choose Arc<T> in order to give library consumers more flexibility.
ArmanRiazi