Identify the correct statement(s) from the following with respect to Spinlock Semaphores:
A. The name refers to busy waiting semaphores.
B. They are not useful when the locks are to be held for a short duration of time.
C. It may require multiple context switches when a process waits on a lock.
D. They are often employed on Uniprocessor systems.
🎥 Video solution / Text Solution of this question is given below:
Spinlocks are busy waiting locks, meaning the thread repeatedly checks until the lock becomes available — so A is correct.
They are actually useful for short duration locks, since blocking (context switch) is costlier — so B is incorrect.
They do not cause context switches, as the waiting is done actively in CPU — so C is incorrect.
Spinlocks are inefficient on uniprocessor systems, because while one thread spins, the other cannot release the lock — so D is incorrect.