COSC1114 Operating Systems Principles

Written Assignment 1

1.  Overview

This assignment focuses on the concepts of Processes, Threads.

2.  Learning outcomes

This assessment is relevant to the Course Learning Outcomes CLOs 2, 4, 5 and 6.

3.  Assessment details

This assessment will determine your ability to

1)   Understand the concepts taught over the first 3 weeks of the course.

2)  Work independently in self-directed study or collaboratively with your teammate to answer all the questions in your own words.

4.  Academic integrity and plagiarism

It is understood by us that many of the algorithms used in this course have common implementations. You are welcome to look at online code examples to understand possible solutions to the set problems. However, what you submit must be your own work and your  submission will be checked and compared with other solutions.

Submitting material generated by an AI tool as your own work constitutes plagiarism and academic dishonesty. DO NOT simply copy other people's work, it is not difficult for us to detect copied work, and we will pursue such cases.

5.  Pair work

This assignment can be done in a team of two students. Teams are expected to collaborate on all aspects of the task, rather than dividing it into independent parts. You may want to brainstorm together, draft solutions jointly, and review each otherÕs work at every stage to ensure mutual understanding and shared responsibility.

Should one team member be unable to complete their contribution by the deadline for any reason, the remaining team member is still responsible for submitting the assignment on time.

Students collaborating in pairs must include their work log (date, student name, tasks completed, and hours spent) as the final page of their PDF submission, to assist markers in resolving any potential disputes.

Please note that extensions and special consideration requests are individual. To apply, you will need to withdraw from the group and do the assignment *individually*. That is, if you want an individual extension or special consideration, you must do the assignment individually. A group extension or special consideration may be granted if all group members are impacted, and this needs to be approved by Course Coordinator.

To form. a team, go to Canvas → People, then select Written assignment 1 group tab. From there, you can drag and drop your name from the list on the left into an available group on the right.

If you have any trouble forming a team this way, please seek help from a teaching staff member during your tutorial session.

6.  Submission

Prepare the answers to this assignment in an electronic format and convert to a single Acrobat PDF (.pdf) file for submission, with the filename being your student number (e.g., S1234567.pdf) containing all the answers to all the questions in this assignment. For pair work, the filename should be the student numbers of both students, concatenated with an underscore (e.g., S1234567_S7654321.pdf). Paper submissions are not accepted.

Your assignment should submit via Canvas → Assignments → Written Assignment 1.

It is your responsibility to correctly submit your files. Please verify that your submission is correctly submitted by downloading what you have submitted to see if your submitted file includes the correct content. Never leave submission to the last minute – you may have difficulty uploading files. You can submit multiple times – a new submission will override any earlier submissions.

However, if your final submission is after the due time, late penalties will apply.

7.  Late submission and extension policy

A penalty of 10% per day of the total available marks will apply for each day being late. After 10 days, you will receive zero marks for the assignment.

If you want to seek an extension of time for assignment submission, you must have a substantial  reason for that, such as unexpected circumstances. Reasons such as, unable to cope with study  load, is not substantial. Also, you must apply for an extension as soon as possible. Last minute extensions cannot be granted unless it attracts special consideration.

Please find out how to apply for special consideration via this link.

Any student wishing an extension must go through the official procedure for applying for extensions and must apply at least a week before the due date. Do not wait till the submission due date to apply for an extension.

8.  Assignment questions

This assignment has 6 questions and students are required to answer all questions.

Tips:

1)   Do not copy from lecture notes or any other sources.

2)   Use your own words and clearly demonstrate your understanding.

3)  The marking guide is designed in alignment with the course content. Your answers should focus on the material covered in this course.

Word Limit:  30 x N, where N being the number of the marks for the question.

For short answer questions, it is generally recommended to keep your answer concise. This helps maintain clarity and ensures that the response is both informative and to the point.

Provide one or two sentences PER MARK, typically ranging from 10 to 20 words per sentence, with no more than three sentences in total.

In average, ONE MARK is 30 words. For a question of N marks, the word limit is 30 x N. For example, if the question is worth 3 marks, the word limit for the question is 90 words. Slightly exceed the word limit will NOT lead to penalty.

Questions: Processes and Threads (20 marks)

1)  (5 marks) Briefly explain the relationship and the difference between Process and Thread. If  you  were  going  to  implement  a  user  program,  discuss  the  factors  when  choosing processes and/or threads for the implementation.

2)  (3 marks) Discuss the principles to protect the OS from poorly written programs or errant users.

3)  (3 marks) Threads can be implemented in user or kernel space. Discuss how the two types of threads work together and the corresponding advantages and disadvantages.

4)  (3 marks) Explain the purpose of a PCB, its placement, and how the operating system manages it, according to what was discussed in class.

5)  (3 marks) Based on what you have learned in this course, discuss how processes

communicate with each other, and how threads communicate with each other. Explain the methods used, and the advantages and disadvantages of each approach.

6)  (3 marks) In a multiprogramming system, there are n jobs running in parallel. Assuming that the I/O wait or blocking probability for each of the jobs are b1, b2, b3, … , bn-1 and bn, respectively, give the CPU utilization of the system (show your working).

9.  Rubric and marking guidelines

Standard rubric for short answer questions:

Fail – Did not answer the question or the answer is largely incorrect or irrelevant.

Pass – Answers are partially correct but significantly incomplete.

Credit – Answers are primarily correct but partially stated, with several inaccuracies or incompletely stated.

Distinction – Answers are mostly accurate and complete, but

1)  may omit some minor details,

2)  contain some minor errors that do not affect the overall understanding.

HD – Answers are accurate and complete.