Device Handler Seek Strategies

 Device Handler Seek Strategies a 15 marks On a hard disk, the queue of track requests is as follows: 19 36 2 27 0 21 18 55 22 Assume that the head starts at track 19. Draw a diagram for arm movement for each of the following seek strategies. (5 marks each) i) FCFS ii) SSTF iii) LOOK b 15 marks Calculate the total number of tracks and the average number of tracks travelled by the head to satisfy the requests in B-Q1-a (Details of the calculations is essential). B-Q2 10 marks Deadlock a 5 marks Describe the four conditions of deadlock in your own word. Give references and cite the sources that you used for this task. b 5 marks Consider a system with five dedicated devices and four processes (process A, B, C and D) that require a maximum of two devices to complete the task. Draw a directed graph of a scenario that demonstrates there is a deadlock in the system. You can use any number of devices (maximum five) and processes (maximum four) in your demonstration. Explain your graph with details. B-Q3 20 marks UNIX a 12 marks Document the following UNIX commands (in clear and concise form): • chmod • cd • mkdir • ls Each of the above commands must be documented to the extent so that the reader of your report could understand how each command works, including the following points: ♣ Brief introduction of the function of the command in your own words (in 2-3 sentences) ♣ The basic syntax of the command, including options. Where appropriate, give a brief description in your own words of at least two options of the command. ♣ At least two examples of the usage of the command that you have used in lab (provide screen capture). Give references and cite the sources that you used for this task. b 8 marks i) Research the similarities and differences between Unix and Linux operating systems. (5 marks) ii) Name three different flavours/distribution of Unix and Linux operating systems. (3 marks) Give references and cite the sources that you used for this task.