Gate Questions Set-4

GATE-2002

Which of the following scheduling algorithms is non-preemptive?

(a) Round Robin (b) First-In First-Out

(c) Multilevel Queue Scheduling

(d) Multilevel Queue Scheduling with Feedback

Ans:-Option-B

The optimal page replacement algorithm will select the page that

(a) Has not been used for the longest time in the past.

(b) Will not be used for the longest time in the future.

(c) Has been used least number of times.

(d) Has been used most number of times.

Ans:- Option-B

GATE-2003

A uni-processor computer system only has two processes, both of which alternate 10 ms CPU bursts with 90 ms I/O bursts. Both the processes were created at nearly the same time. The I/O of both processes can proceed in parallel. Which of the following scheduling strategies will result in the least CPU utilization (over a long period of time) for this system?

(a) First come first served scheduling

(b) Shortest remaining time first scheduling

(c) Static priority scheduling with different priorities for the two processes

(d) Round robin scheduling with a time quantum of 5 ms

Ans:-Option-A

Consider the following set of processes, with the arrival times and the CPU-burst
times given in milliseconds.



What is the average turnaround time for these processes with the preemptive
shortest remaining processing time first (SRPT) algorithm?
(a) 5.50 (b) 5.75 (c) 6.00 (d) 6.25