1. ICS 143 Principles of Operating Systems
Discussion Section Week 6

2. Today Announcements Programming Assignment Mid-term Solutions
11/16/2018

3. Announcements Programming Assignment Homework #3:
Out now on class website (Homework page)
Due Wed, 10 June 2015, 11:55pm via EEE Dropbox
Homework #3:
(delayed) Out early next week
11/16/2018

4. Programming Assignment
Follow project description on class website (Homework page):
Individual submission – everyone gets to code!
It’s ok to discuss ideas, but everyone must submit their own code
Goal is to implement different schedulers:
First-Come, First-Served (FCFS)
Shortest Remaining Time First (SRTF)
Aka preemptive Shortest Job First (SJF)
Extra credit: Proportional Share (PS)
Pre-allocates certain amount of CPU time to each process
Every job has a weight, and jobs receive a share proportional to the weight
11/16/2018

5. Programming Assignment (2)
11/16/2018

6. Programming Assignment (3)
Scheduler.java:
Abstract interface each scheduler has to follow
FCFSScheduler.java:
Skeleton class to implement FCFS scheduling
SRTFScheduler.java:
Skeleton class to implement SRTF scheduling
PSScheduler.java:
Skeleton class to implement PS scheduling
Makefile:
Instructions to compile your source code (Linux)
Tester.java:
Class used to test your code
11/16/2018

7. Programming Assignment (4)
FCFSScheduler::schedule:
Parse input file (file name given as inputFile string)
Schedule jobs
Write output file (file name given as outputFile string)
/**
* First-come-first-serve scheduler. */
public class FCFSScheduler implements Scheduler {
@Override
public void schedule(String inputFile, String outputFile) {
// implement your scheduler here.
// write the scheduler output to outputFile} }
11/16/2018

8. Programming Assignment (5)
Input: text file
One incoming process per line
<process-id> <arrival-time> <burst-time> <share>
Output: text file
One scheduled process per line
<process-id> <finish-time> <wait-time> <turnaround-time>
Last line:
<average-wait-time> <average-turnaround-time>
Submission: .zip package via EEE DropBox
11/16/2018

9. Programming Assignment (6)
Black-box testing via grade.sh on Linux machine:
Public tests and expected output provided
Will test on public / private tests to make sure your code works
Grading
FCFS: 30 points
SRTF: 50 points
1-Page Report: 20 points + 5 bonus points (PS)
(Extra) PS: bonus points
11/16/2018

10. Programming Assignment (7)
Black-box testing via grade.sh on Linux machine:
Your responsibility to make sure that your code compiles and runs in Linux
If you want, you can simulate our exact grading procedure:
Get the exact same software environment:
Download and install VirtualBox for Linux
Download and install Ubuntu LTS inside VirtualBox
Download and install openjdk-7-jdk
Run the exact same script:
Execute grade.sh
Verify output and grade
(Detailed instructions in programming_assignment.pdf)
11/16/2018

11. Programming Assignment (8)
Opportunity to learn how to use git / GitHub:
Instead of downloading .zip, fork the repo!
Create your own branches, have a local/remote copy of your code progress
You can contribute your own public tests:
Fork & clone the repo
Add some public tests
Send a pull request
11/16/2018