GATE 2006 CPU scheduling PYQ

GATE 2006

The arrival time, priority, and durations of the  CPU and I/O bursts for each of three processes  P1, P2 and P3 are given in the table below. Each  process has a CPU burst followed by an I/O burst  followed by another CPU burst. Assume that each  process has its own I/O resource. 

Process

Arrival Time

Priority

Burst Duration

 

CPU

I/O

CPU

P1

0

2

1

5

3

P2

2

3 (lowest)

3

3

1

P3

3

1 (highest)

2

3

1

The multi-programmed operating system uses  preemptive priority scheduling. What are the  finish times of the processes P1, P2 and P3?  
(a) 11, 15, 9 
(b) 10, 15, 9  
(c) 11, 16, 10 
(d) 12, 17, 11