超星 - Chapter 5 Process synchronization

单选题

Which of the following conditions must be satisfied to solve the critical section problem?

A. Mutual Exclusion
B. Progress
C. Bounded Waiting
D. All of the mentioned

单选题

Mutual exclusion implies that ____________

A. if a process is executing in its critical section, then no other process must be executing in their critical sections
B. if a process is executing in its critical section, then other processes must be executing in their critical sections
C. if a process is executing in its critical section, then all the resources of the system must be blocked until it finishes execution
D. none of the mentioned

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单选题

Bounded waiting implies that there exists a bound on the number of times a process is allowed to enter its critical section ____________

A. after a process has made a request to enter its critical section and before the request is granted
B. when another process is in its critical section
C. before a process has made a request to enter its critical section
D. none of the mentioned

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单选题

An un-interruptible unit is known as ____________

A. single
B. atomic
C. static
D. none of the mentioned

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单选题

Each process Pi, i = 0,1,2,3,……,9 is coded as followsThe code for P10 is identical except that it uses V(mutex) instead of P(mutex). What is the largest number of processes that can be inside the critical section at any moment (the mutex being initialized to 1)?

A. 1
B. 2
C. 3
D. None of the mentioned

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单选题

The following program consists of 3 concurrent processes and 3 binary semaphores. The semaphores are initialized as S0 = 1, S1 = 0, S2 = 0.How many times will P0 print ‘0’?

At least twice
B. Exactly twice
C. Exactly thrice
D. Exactly once

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单选题

The code that changes the value of the semaphore is ____________

A. remainder section code
B. non – critical section code
C. critical section code
D. none of the mentioned

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单选题

If the semaphore value is negative ____________

A. its magnitude is the number of processes waiting on that semaphore
B. it is invalid
C. no operation can be further performed on it until the signal operation is performed on it
D. none of the mentioned

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单选题

The wait operation of the semaphore basically works on the basic _______ system call.

A. stop()
B. block()
C. hold()
D. wait()

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单选题

The signal operation of the semaphore basically works on the basic _______ system call

A. continue()
B. wakeup()
C. getup()
D. start()

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