Operating Systems Lesson 4
Question 4– Given it takes 1.75 mins to travel from one track to the next of a hard drive; that the arm is originally positioned at track 15 moving toward the lowers number tracks; and that you are using the LOOK scheduling policy; compute the total seek time to schedule time to schedule the following requests – 4, 40, 35, 11, 14, and 7. Assume all requests are initially present in the wait queue. (Ignore rational time and transfer time, just consider seek time.)
Question 9– Describe how to implement a RAID Level 2 system would be beneficial to a university payroll system. In your own words describe the advantages and disadvantages of such a system, if any, in that environment, and if appropriate, suggest an alternative RAID system and explain your reasoning.
Question 5– Image one real life example of each: a multi-file volume and a multi-volume file. Include a description of the media used for storage and a general description of the data in the file.
Question 10– The following is an access verification technique, listing several files and the access allowed for a single user. Identify the control technique used here, and for each, explain the type of access allowed.
- File_1 R-E-
- File_12 RWE-
- File_13 RE—
- File_14 –E-
Question 13– Devise a way to compress the following list of names using a lossless technique similar to that shown in table 8.6 for repeated terms. Describe your method and show the compressed list. Explain the characteristics that make your technique lossless (and not lossy).