Operating System (3140702) MCQs

MCQs of I/O Management & Disk scheduling

Showing 11 to 20 out of 40 Questions
11.
Whenever a process needs I/O to or from a disk it issues a ______________
(a) system call to the CPU
(b) system call to the operating system
(c) a special procedure
(d) All of the mentioned
Answer:

Option (b)

12.
If a process needs I/O to or from a disk, and if the drive or controller is busy then ____________
(a) the request will not be processed and will be ignored completely
(b) the request will be not be placed
(c) the request will be placed in the queue of pending requests for that drive
(d) None of the mentioned
Answer:

Option (c)

13.
Consider a disk queue with requests for I/O to blocks on cylinders. 98 183 37 122 14 124 65 67. Considering FCFS (first cum first served) scheduling, the total number of head movements is, if the disk head is initially at 53 is?
(a) 600
(b) 620
(c) 640
(d) 650
Answer:

Option (c)

14.
Consider a disk queue with requests for I/O to blocks on cylinders. 98 183 37 122 14 124 65 67. Considering SSTF (shortest seek time first) scheduling, the total number of head movements is, if the disk head is initially at 53 is?
(a) 224
(b) 236
(c) 240
(d) 245
Answer:

Option (b)

15.
SSTF algorithm, like SJF __________ of some requests.
(a) may cause starvation
(b) will cause starvation
(c) does not cause starvation
(d) causes aging
Answer:

Option (a)

16.
In the ______ algorithm, the disk arm starts at one end of the disk and moves toward the other end, servicing requests till the other end of the disk. At the other end, the direction is reversed and servicing continues.
(a) LOOK
(b) SCAN
(c) C-SCAN
(d) C-LOOK
Answer:

Option (b)

17.
In the _______ algorithm, the disk head moves from one end to the other, servicing requests along the way. When the head reaches the other end, it immediately returns to the beginning of the disk without servicing any requests on the return trip.
(a) LOOK
(b) SCAN
(c) C-SCAN
(d) C-LOOK
Answer:

Option (c)

18.
In the ______ algorithm, the disk arm goes as far as the final request in each direction, then reverses direction immediately without going to the end of the disk.
(a) LOOK
(b) SCAN
(c) C-SCAN
(d) C-LOOK
Answer:

Option (a)

19.
The data structure for a sector typically contains ____________
(a) header
(b) trailer
(c) data area
(d) All of the mentioned
Answer:

Option (d)

20.
The _______ program initializes all aspects of the system, from CPU registers to device controllers and the contents of main memory, and then starts the operating system.
(a) main
(b) bootloader
(c) bootstrap
(d) rom
Answer:

Option (c)

Showing 11 to 20 out of 40 Questions