Test Papers / Previous Question Papers of IGNOU CS13 Operating Systems December 2002

MCA (III Yr)
Term-End Examination

December, 2002

CS13 : Operating Systems

Time: 3 hours
Maximum Marks: 75

1. (a) Write and explain one of the deadlock detection algorithms and evaluate its performance.

(b) Explain the logic of Dekker’s solution to the mutual-exclusion problem and also discuss whether it is suitable to be implemented in a multiprocessors system with shared memory.

(c) Describe Belady’s anomaly and provide an example that illustrates anomalous behaviors of FIFO.

2 (a) Compare and contrast implicit tasking and Explicit tasking of the processes. Also highlight the advantages of Explicit tasking.

(b) The identified disadvantages of semaphores are
(i)Semaphores are unstructured
(ii) Semaphores do not support data abstraction.

3 (a) Write short notes on the following:
(i) Two-phase locking
(ii) Wait-die and Wound-wait
(iii)Busy waiting

(b) Compare and contrast Remote Procedure Call (RPC) With Message passing in Distributed O/S environment.

4 (a) Explain the difference between internal fragmentation and external fragmentation. Which one occurs in paging system? Also, explain through a diagram, the principle of address translation in paging scheme.

(b) What are PAGE MAP TABLE (PMT), MEMORY MAP TABLE (MMT) and FILE MAP TABLE (FMT)? Explain how they are associated in the management of virtual memory.

5 (a) Explain why shared-bus multiprocessors are generally regarded as having limited scalability.

(b) State and discuss the differences in resource management requirements between Uniprocessor and Multiprocessor operating systems.

(c) What is disk caching? What are its advantages?

6 Wrote short notes on:
(i) Bell-LaPadula Model
(ii) Chaining and Indexing allocation strategies of disk space
(iii)Rivest, Shamir, Adelman (RSA) algorithm