Operating Systems - Dec 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) What is OS? What are the common tasks performed by OS and when they are performed?(7 marks) 1 (b) Explain turn around time in batch processing system.(6 marks) 1 (c) Define distribution system. Give the key concepts and techniques used in distributed O.S.(7 marks) 2 (a) Explain with basic structure used for system generation in configuring and installing supervisor.(7 marks) 2 (b) Explain with a figure the working of a two layered O.S. structure.(6 marks) 2 (c) With a neat diagram, explain the working of a micro kernel based O.S.(7 marks) 3 (a) Define a process. List the different fields of a process control blocks.(6 marks) 3 (b) Explain the four fundamental states of process with state transition diagram.(7 marks) 3 (c) What are the advantages of threads over process? Explain kernel level threads.(7 marks) 4 (a) Explain the working of a buddy system allocator.(6 marks) 4 (b) Give the comparison of contiguous and non-contiguous memory allocation.(6 marks) 4 (c) Explain first fit and best fit technique used to perform a fresh allocation from a free list.(8 marks) 5 (a) Explain what are the functions performed by paging hardware.(6 marks) 5 (b) What are the functions performed by VM handler? Give the data structure of VM handler.(6 marks) 5 (c) Consider the page reference string 5,4,3,2,1,43,5,4,3,2,1,5. How many page faults would occur for the following page replacement policies assuming 3 frames?
(i) FIFO (ii) LRU(8 marks) 6 (a) What are the facilities provided by the file system and the input-output control system?(6 marks) 6 (b) With a figure explain the working of a linked allocation of disk space.(7 marks) 6 (c) Explain the interface between file system and IOCS.(7 marks) 7 (a) With diagram explain the working of a long, medium and short term scheduling in a time sharing system.(10 marks) 7 (b) For the following given process for scheduling.