University of Sargodha MS I" Term Examination 2014 Subside: Computer Science Paper: Advanced Operating System (CS-5611) Time Altered: 3 Hours

University of Sargodha

MS I" Term Examination 2014

Subside: Computer Science Paper: Advanced Operating System (CS-5611)

Time Altered: 3 Hours

Session: 2014616 Spring

ustadni.

Maximum Marks: 80

Note:

Objective part is compulsory, Attempt any four questions fromsubjective part.

Objective Part

Q.1 Write short answers of the following.

1. What is multi-threading?

Il. What is ORPHAN call?

I!!. Define Translation Look Aside Buffer (TLB). /

IV. What is a context-switch?

V. What is a process?

VI. Define and differentiate between a file and directory.

VIl. What is a critical section?

VIII. Define user mode and kemel mode.

Subjective Part

Q.2

(a) List and briefly describe any 5 of the typical services provided by an OS. (8) -

(b) Briefly explain the system calls and software traps. Describe how the work. (8) -

Q.3

(a) What is race condition? What is Mutual exclusion? Explain the mutual exclusion with busy

waiting. Briefly describe the spin lock. (10]

(b) Describe the binary semaphore and counting semaphore. Explain with code block. (6)

(2*8)

(a) Election Algorithms

namely contiguous allocation, linked allocation, and indexed allocation. Briefly describe each

approach, identifying the strengths and weaknesses of each. Draw a figure where necessary. (4+6+6)

Q.7

(a) Define each of swapping and paging, and clarify their respective roles in OS memory

management. (8)

(b) Define, Compare and contrast the paging and segmentation approaches to memory management,

making sure to identify the strengths and weaknesses of iSit Website: stadni.com