Operating Systems - Dec 2013
Computer Science Engg. (Semester 5)
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 storage devices hierachy, with a neat diagram(8 marks) 1 (b) Explain the following in brief:
(i) Real time embedded system
(ii) Multimedia systems.(6 marks) 1 (c) Write the system call sequence to copy a file from source to destination.(6 marks) 2 (a) Explain the implementation of producer consumer processes using bounded buffer in shared memory system.(8 marks) 2 (b) Explain the different multithreading models. With neat sketch(6 marks) 2 (c) Consider the following set of processes
|Process||Arrival time (ms)||Burst time (ms)|
Draw Gantt charts and calculate average waiting time and average turnaround time using non-preemptive SJF and preemptive SJF scheduling algorithms.(6 marks) 3 (a) Explain the critical section problem list and explain the requirements to be met by a solution to critical section problem(6 marks) 3 (b) Write and explain with respect to synchronization hardware
(i) The definition of TestAndSet() instruction
(ii) Mutual-exclusion implementation with TestAndSet()(6 marks) 3 (c) Explain the monitor solution to dining-philosopher problem.(8 marks) 4 (a) Explain the resource allocation graph with an example.(4 marks) 4 (b) Explain the Banker's algorithm for deadlock avoidance.(10 marks) 4 (c) Explain the following methods to recover from deadlock
(i) Process termination
(ii) Resource preemption(6 marks) 5 (a) Draw and explain the multistep processing of a user program.(8 marks) 5 (b) In the paging scheme with TLB. It takes 20 ns to search the TLB and 100 ns to access memory. Find the effective access time and percentage showdown in memory access time if
(i) Hit ratio is 80%
(ii) Hit ratio is 98% (4 marks) 5 (c) Prove that Belady's anomaly exists for the following reference string using FIFO algorithm when numbers of frame used are 3 and 4, 1, 2, 3, 4, 1, 2, 5, 1, 2, 3, 4, 5(8 marks) 6 (a) List the common file types with their usual extension and function.(8 marks) 6 (b) Explain the typical file-control block, with a neat sketch.(6 marks) 6 (c) Explain any two file allocation methods, in brief.(6 marks) 7 (a) With a neat sketch, explain the structure of moving -head disk mechanism.(6 marks) 7 (b) Suppose that a disk has 50 cylinder named 0 to 49. The read/write head is currently serving at cylinder 15. The queue pending requests are in order
4, 40, 11, 35, 7, 14
Show the graphical representation and calculate average head movement using C-SCAN and C-LOOK scheduling algorithms.(8 marks) 7 (c) Explain the following operations in access matrix with an example of each
(iii) Limited copy.(6 marks) 8 (a) Explain the components of Linux system, with a neat diagram.(6 marks) 8 (b) Explain the following with reference to process management in Linux
(i) Process identity
(ii) Process context (8 marks) 8 (b) With a neat daigram, explain the memory layout for ELF programs in Linux.(6 marks)