The difference between Mutex and a RwLock is that RwLock<T> requires more bounds for T to
be thread safe; Mutex requires T: Send to be Sync while on the other hand RwLock requires
T: Send + Sync to be Sync.
To begin with, Mutex is a method of locking, to control access to shared resources. At the same time, only one thread
can access data that is protected inside the mutex. If another thread wants to lock a resource and the mutex
is in locked state, the thread hangs until the locked thread releases the mutex; threads using mutex lack read concurrency.
Next, RwLock is more complex then a Mutex hence, the performence is poor then a mutex. When there are more read
operations and fewer write operations, read-write locks are efficient and can be used to improve thread read concurrency.
After summing up all of the facts, use Mutex when there are more or equal amount of write operations and a RwLock when
there are more read operations.