Operating Systems - Jun 2014

Electronics & Communication (Semester 6)

TOTAL MARKS: 100
TOTAL TIME: 3 HOURS (1) Question 1 is compulsory.
(2) Attempt any four from the remaining questions.
(3) Assume data wherever required.
(4) Figures to the right indicate full marks. 1 (a) Explain the goal of an operating system.(6 marks) 1 (b) Explain the designer's view of operating system.(4 marks) 1 (c) Explain modes of performing I/O operations.(5 marks) 1 (d) Explain the benefits / features of distributed operating system.(5 marks) 2 (a) Explain the functions of an operating system.(5 marks) 2 (b) Explain the layered design of operating system.(8 marks) 2 (c) Explain the concept of VMOS with example.(7 marks) 3 (a) Explain the contents of process control block.(6 marks) 3 (b) List the different types of process interaction and explain them in brief.(6 marks) 3 (c) Explain with a neat diagram, the different states of process in UNIX operating system.(8 marks) 4 (a) Describe static and dynamic memory allocation.(4 marks) 4 (b) Compare the contiguous and non-contiguous memory allocation.(4 marks) 4 (c) What is boundary tag? Explain merging of free areas using boundary tags?(8 marks) 4 (d) Explain the lazy buddy allocator.(4 marks) 5 (a) Explain the important concepts in the operation of demand paging.(12 marks) 5 (b) Find the number of page faults for following page reference string, using the FIFO and LRU page replacement policies.
Reference string: 5,4,3,2,1,4,3,5,4,3,2,1,5. (Assume page frames=3).(8 marks) 6 (a) Describe the different operations performed of files.(8 marks) 6 (b) Explain the organization of sequential access and direct access files.(8 marks) 6 (c) Describe file system actions during a file operation.(4 marks) 7 (a) Compute mean turn around time and mean weighted turn around time for following set of process, using FCFS and SRN scheduling.