Operating systems exams - multiple choice questions (MCQ) and answers, Objective type questions, OS exam questions
1. Which of the following statements is/are true?
(a) Shortest Job Next (SJN) is the best preemptive scheduling algorithm in terms of turnaround time
(b) First Come First Serve (FCFS) can suffer from starvation
(c) Priority scheduling is the most general scheduling algorithm
(d) None of the above.
2. The working set of a process
(a) is statically determined based on the code
(b) is impossible to determine at runtime
(c) can change as the process executes
(d) is set of pages in the virtual address space of the secondary memory device.
3. Which of the following is an advantage of Direct Memory Access (DMA)?
(a) It requires fewer memory copies
(b) Increases the speed of the CPU
(c) Increases the speed of the data bus
(d) Increases the performance of the system by allowing more things to happen at once
4. Which one of the following is one of the three ways in which context-switching can happen in a non-preemptive scheduler?
(a) The user code can request an I/O operation
(b) Through killing a process
(c) Restart the system process
(d) None of the above
5. Buffering is useful because:
(a) It makes it seem like there is more memory in the machine
(b) It allows devices and the CPU to operate asynchronously
(c) It requires fewer memory copies
(d) It increases the file system performance
Click here for Answers:
1. – (C)
SJN is a non-preemptive algorithm. FCFS does not suffer from starvation.
2. – (C)
Working set
Working set is a concept in computer science which defines the amount of memory that a process requires in a given time interval.
3. – (D)
4. – (A)
Three ways:
1) The user code can execute a yield() system call.
2) The user code can request an I/O operation.
3) The user code can request a wait() operation for another thread (such as thread-join).5. – (B)
No comments:
Post a Comment