CSS 430: Operating Systems Assignments

Language

We use Java to program all assignments except Program 1. Program 1 consists of two sub problems, one practising Linux system calls in C or C++ and the other using Java. Programs 2 through to 3 implement in Java an operating system simulator, called ThreadOS step by step through assignments.

Operating Systems

The operating system I recommend for all assignments is Linux (UW1-320). This is because Program 1 uses Linux system calls; the ThreadOS simulator is stored in the css430 account at UW1-320; and the grader will grade your assignments using a UW1-320 machine.

There are more reasons why this course recommends Unix-based operating systems: (1) many companies and institutions use Unix machines as their servers, while their client machines are Windows, (2) most computation-intensive and concurrent applications are based on Unix, (3) many OS design techniques and concepts came from Unix, (4) the Linux Kernel code is free to obtain and is commented in many reference books, and (5) it is easy to coordinate and submit a batch of jobs through shell scripting. While you are repeatedly using Unix for your assignment work, you will gradually get familiar with Unix commands.

UW1-320 Laboratory

Here is a procedure to log on one of the UW1-320 Linux machines and upload your files:

1. To use a console of any UW1-320 machine, enter UW1-320 Linux Laboratory with your student ID card and log into any machine with your UW Net ID and the corresponding password.
2. To remotely log into a UW1-320 machine, use ssh and establish a connection to uw1-320-lab.uwb.edu.
   You will automatically got one of the lab machines and see your home directory immediately.
3. To transfer files to the UW-320 file server
   1. From an off-campus Linux machine: use the sftp command and establish a connection to uw1-320-lab.uwb.edu.
   2. From a Windows machine: use SSH Tectia Client, downloadable at: https://www.washington.edu/uware/tectia/
   3. From a Mac: use Fugu 1.2, downloadable at http://rsug.itd.umich.edu/software/fugu/

The Source for Java Technology

1. Java Tutorials: helps you run Java programs at Windows, Unix, and Mac, introduces the Java language, and lists essential Java classes.
2. Java SE Version 6, API documentation: lists all necessary Java API classes. You will frequently visit this page to review what classes are ready to use for your assignment programs.
3. Java SE 6 : allows you to download the Java SE version 6 platform

Java Programming Environments

• Compile-time errors: The javac compiler points out where your source program has syntax errors. Carefully look at its error messages. You will find out code line numbers that have syntax errors. Open your source code, go to those lines, and fix your bugs.
• Run-time errors: The java virtual machine points out where your compiled program has run-time errors. Carefully look at its error messages. You will find out your source code's line numbers that have run-time errors. Open your source code, go to those lines, and fix your bugs.
• Debugging tools: The following three may be helpful to develop your Java program. However, please note that they may not be always useful when you develop multi-threaded programs. (Most assignments are multi-threaded programs)
  1. Jcreator
  2. JPad Pro
  3. NetBeansIDE (available at UW1-320)
  4. Eclipse (available at UW1-320)

1. Program 1 exercises basic linux system-call programming and also implements a simple shell on our operating system simulator, ThreadOS.
2. Program 2 implements a multilevel-queue-based scheduler in Java. ThreadOS.
3. Program 3 realizes inter-threads synchronization in ThreadOS in order to arbitrate disk read/write requests from multiple threads.
4. Program 4 implements a disk cache based on the second-chance algorithm. ThreadOS.
5. Project constructs a Unix file system on top of ThreadOS.

Submissions

• Hardcopy must include your report, program listing, and execution output. Your report must include specifications, explanations, and/or illustrations of algorithm and data structures you used, and summarize your consideration of test results, (i.e., do they make sense?). Note that you do not have to repeat writing all the assignment specification. Use a typewriter font (e.g. courier new) for your source code and execution output.
  
  There will be no hardcopy required (or accepted) for assignments during Autumn 2011 unless specifically called for in the individual assignment pages
  
  
• Softcopy must be a tar archived file that includes only your java source code. Your code should compile and run properly using g++ and/or javac within the linux environment at uw1-320-lab.uwb.edu since the grader tests them only using that environment. Follow the softcopy submission procedure shown below:
  • To log in the uw1-320-lab Linux laboratory:

       ssh your_linux_account@uw1-320-lab.uwb.edu
    

  • To compile your Java program, type:

       javac your_program1.java your_program2.java ...
    

    If there are no compiler errors, this will create your_program1.class, your_program2.class, ...

  • To run your Java program, type:

       java your_program1
    

    To run our ThreadOS simulator with your assignment, type:

       java Boot
    

    Submit your source files for any given assignment using the "Browse" button on the associated Assignment Dropbox page for that assignment.
  • To archive your source programs in a file named "program1.tar":

       tar -cvf - your_program1.java your_program2.java > program1.tar
    
          *    * *                  *                  * *
      (A space must be inserted at each of these * marks.)
    

    
    WARNING: if you do not understand what the above command says, MAKE VERY SURE you have backup copies of your program, chances are you will overwrite your program when creating the tar. Remember to download/un-tar your submission to make sure everything is correct. If your submission is corrupted or in-complete, you will receive a zero for the assignment. I repeat, if we cannot untar your submission, or if you submitted a zipped archive, you will receive a zero for the assignment.
    
  • To submit your archived file "program1.tar" including your homework assignment 1, visit our Catalyst CollectIt (for Assignment) website. Don't email your softcopy to me. You may repeat submitting a newer copy as many times as you wish. We will only look at your latest submission.

• Assignments are due at the beginning of lecture for both your hardcopy and softcopy on the specified date. No late programs will be accepted unless you provide me with a proof showing that you have been under an emergency circumstance. No matter the circumstances, it is always best to turn in something.

Grading

Acknowledgment