(b) Critical regions need to be protected in a system running multiple parallel processes. Semaphores represent...

  

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(b) Critical regions need to be protected in a system running multiple parallel processes. Semaphores represent one way in which access to critical regions are protected. A semaphore A used to access a given critical region, three processes P1, P2, and P3, and the following sequence of Semaphore operations Test(A) and Increment(A). Determine which process is running in the critical region, which process(es) are blocked, and the value of A, for each step in the sequence of operations by filling in the table below. State Active No. 0 1 234 Process P2 P1 P2 P3 Operation - Test(A) Test(A) Increment(A) Test(A) Process Accessing Critical Region Process(es) blocked on A Value of A 1 (12/100) (b) Critical regions need to be protected in a system running multiple parallel processes. Semaphores represent one way in which access to critical regions are protected. A semaphore A used to access a given critical region, three processes P1, P2, and P3, and the following sequence of Semaphore operations Test(A) and Increment(A). Determine which process is running in the critical region, which process(es) are blocked, and the value of A, for each step in the sequence of operations by filling in the table below. State Active No. 0 1 234 Process P2 P1 P2 P3 Operation - Test(A) Test(A) Increment(A) Test(A) Process Accessing Critical Region Process(es) blocked on A Value of A 1 (12/100)