CS 3733 Operating Systems, Fall 2008 Recitation Session 4

Wednesday, September 24.
In this session you will continue using the Process Scheduling Simulator.

• Log on to your Linux Account.
• Create a rec04 subdirectory of the assign2 directory that you created in the last recitation session.
• Copy all of the files from the assign2/rec03 directory into rec04.
  Erase any file that has a .gif extension.
• In the rec04 directory, execute runps to make sure the simulator still works.
  Exit the simulator.
• Modify the myexp.exp file to have 5 run lines that will use the following algorithms:
  FCFS, SJF, RR 1, RR 5, and RR 10. On each run line, make sure that both the algorithm and key are appropriately set.
• Now modify the myrun.run file so that there will be a total of 20 processes with the following properties:
  • All processes arrive at time 0.0.
  • All processes have a constant duration of 100.
  • All have constant I/O bursts of 10.
  • All have basepriority 1.0.
  • The first 10 processes have CPU bursts uniformly distributed between 2 and 8.
  • The last 10 processes have CPU bursts uniformly distributed between 30 and 40.
  • Do not change the seed line of the run file.
• Run the simulator and create a log file containing the tabular data and 5 Gantt charts, one for each run.
• Using a text editor, create a text file containing a paragraph describing which of the experiments has the best average waiting time. Also, compare the trend in the Round Robin experiments as the quantum increases. For large values of the quantum, Round Robin will perform like one of the other two runs. Which one? How large would the quantum have to be.
• Edit the logfile.html file and insert your paragraph near the end of the file. Put it right before the line beginning "Process Schedule Log for ...". Insert <p> before the start and after the end of the paragraph. Look at the log file in a browser to see that your paragraph is readable.
• Make a rec04 subdirectory of you public_html/cs3733 directory.
• Copy the logfile.html and all of the .gif files into this directory.
• Put a link on your CS 3733 web page to logfile.html.
• Demonstrate to the TA that you have this link and that it works correctly.