Cs-13

ADCA / MCA (Iil Year) Term-End Exarnination December, 2OO7

CS-13 : OPERATINGSYSTEMS Maximum Msrks : 75

Time : 3 hours Nofe ,

1.

(a)

Qu estion number 1 is compulsory. three questions from the rest'

Define

deadlock with

example.

Answer sny

List

the

four

necessary conditions for the deadlock occurrence' Also explain deadlock prevention methods' (b)

I

Does it f)escribe Belady's anomaly with an example' occur in all page replacement algorithms ?

(c)

Explain Prod ucers/Consumers problem in concurrent programming, with an examPle'

(d)

Define the terms mutual exclusion and semaphores with examples.

(e)

What

is thrashing

?

Explain

its

causes' Give

exarnples.

CS-13

P.T.O.

2 . (a)

Explain Ricart and Agarwala's Algorithm for ordering of events in distributed operating system environment

(b)

If memory access time is zso nsec; search time in TLB is 25 nsec; hit ratio is gOo/o;calculate effective memory accesstime.

3

(c)

write the types of multiprocessor os.

5

(a)

For the following processes and CpU burst time

3.

(Nofe

: AII the proces.sesarriued at

the s,,me

time) Processes

(i)

Bursttime

P1

1

P2

4

P3

3

P4

2

Draw Gantt charts showing the execution of processes for

(ii)

(a)

SJF

(b)

Round Robin scheduling (quantum

Calculate the waiting time and turnaround time of each process for above scheduling algorithms.

(b)

Dekker's solution problem, with an example.

(c)

Explain Access-matrix model for protection, with an example.

C S - 13

Explain

to

mutual

exclusion

3

4.

(a)

Explain the concept of paged segmentation. What are its overheads ?

(b)

(c)

5.

(a)

List and explain the disk allocation methods in an operating system.

5

Explain take-grant model for protection of a system.

5

[-ist '

(b)

the

similarity

and

differences

between

multiprocessor and distributed systems. Explain the concept of working set model with an example.

(c)

Explain single-stage and multi-stage interconnection networks with examples.

CS-13

19,000