CSCI 3120 Chapter 6 Part 2 Final Exam Questions 100% Well Answered.

Hardware could be utilized to solve the critical section problem, three forms of hardware solutions include: - Answer 1. Memory Barriers 2. Hardware Instructions 3. Atomic variables Hardware based solutions to the critical section problem are complicated as well as - Answer generally inaccessible to application programmers Mutex Lock - Answer A process must acquire the lock before entering a critical section; it them releases the lock when it exits the critical section aquire() - Answer aquires the lock release() - Answer releases the lock Only if a lock is available - Answer a call to acquire() succeeds A process that attempts to acquire a unavailable lock - Answer is blocked until the lock is released Spinlocks are nice because - Answer we dont need to do a context switch when a process must wait on a lock, we can just spin until the lock becomes available A semaphore S is an integer variable that, apart from initialization, is accessed - Answer only through two indivisible (atomic) operations: wait() and signal() Two types of semaphores - Answer Binary Semaphore (similar to mutex lock) - int range from 0 to 1 Counting semaphore - int 0 to N Counting semaphores can be used to - Answer control access to a finite number of resources Wait() does what - Answer used when process wishes to use resource, decrements the semaphore