关于boost :: lock_guard和boost :: unique_lock

Question

I was hoping someone could tell me if my understanding on the following 3 locks is correct and possibly add to it. my main concern is speed with minimum overhead.

• boost::lock_guard
• boost::unique_lock
• boost::scoped_lock

boost::lock_guard is the lightest kind of a lock and is only shared amongst members of a process. The unique_lock is an improved version of lock_guard with more functionality. The scoped_lock allows locking across different processes.The scoped_lock is the heaviest of all locks.Is my understanding correct. The thread here however states that scoped_lock is similar to unique_lock. if so does that mean scoped_lock is as heavy as unique_lock ?

Answer 1

If what you mean by heavy is the amount of overhead, then yes scoped_lock is as heavy as unique_lock, because they're the same thing. According to this , a unique lock has a few more features than lock_guard, at the expense of a bit of overhead.