Homework 2 - Scheduling algorithms in GO

Abstract
The goal of this assignment is to write a program in GO that reads an input file containing several
configuration parameters to simulate First-Come First-Served, preemptive Shortest Job First, and RoundRobin CPU scheduling algorithms. The output will reflect the results of the configured CPU scheduling
algorithm to a specified output file.
1 Objectives
The objectives of this assignment are to simulate the CPU scheduline of several processes for the configured First-Come First-Served, preemptive Shortest Job First, and Round-Robin CPU scheduling algorithms.
Therefore the algorithm will need to be selected/configured as will the processes and their durations and
burst cycles, as appropriate.
1.1 Algorithms
1.1.1 First-Come First-Served
The First-Come First-Served algorithm is just that: processes are allocated the CPU in the order in which
they arrive and run until completion or termination.
1.1.2 Preemptive Shortest Job First
The Preemptive Shortest Job First selects the process for execution which has the smallest amount of time
remaining until completion. Therefore, a process with a budget or expected time of 2 time units will be
scheduled ahead of a process with 6 time units.
1.1.3 Round-Robin
Round-Robin was originally built for time-sharing systems. It works on the premise of providing a rigorous
enforcement of an interrupt every configured time interval, then swapping to the next task in the process list
at the moment of the interrupt. This scheduling algorithm treats the process list as a circular list until each
process is complete. New processes can be added infinitum.
Note that the Round-Robin algorithm requires a configuration of the time quantum for the period of time
used for the process to be in the CPU. Once the period expires the next process in the list will have CPU
resources until its time quantum expires.
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2 Specifications
2.1 Inputs
The input file will be passed as the first command line argument. Also the program should ignore everything
on a line after a # mark and ignore additional spaces in the input file.
processcount 2 # Read 2 processes
runfor 15 # Run for 15 time units
use rr # Can be fcfs, sjf, or rr
quantum 2 # Time quantum, only if using rr
process name P1 arrival 3 burst 5
process name P2 arrival 0 burst 9
end
There is no requirement to process blank lines.
The input files are as follows:
Table 1: Input Test Files
Filename Description
c2-fcfs.in 2 processes scheduled First-Come First-Served
c2-rr.in 2 processes scheduled Round-Robin
c2-sjf.in 2 processes scheduled preemptive Shortest Job First
c5-fcfs.in 5 processes scheduled First-Come First-Served
c5-rr.in 5 processes scheduled Round-Robin
c5-sjf.in 5 processes scheduled preemptive Shortest Job First
c10-fcfs.in 10 processes scheduled First-Come First-Served
c10-rr.in 10 processes scheduled Round-Robin
c10-sjf.in 10 processes scheduled preemptive Shortest Job First
2.1.1 Command Line Inputs
The command line inputs or cli are the input file name as the first parameter and the output file name as the
second parameter. For example:
./pa1 c5-fcfs.in c5-fcfs.stu
where the files’ extensions correspond to input and student. Review the pa1Test.sh file in the assignment
ZIP file for more examples.
2
2.2 Outputs
The output of each schedule shall be formatted as shown below. Note that the output below corresponds to
the input file shown above. You can also review the files that have the base extension for each test cases’
expected outputs.
2 processes
Using Round-Robin
Quantum 2
Time 0 : P2 arrived
Time 0 : P2 selected (burst 9)
Time 2 : P2 selected (burst 7)
Time 3 : P1 arrived
Time 4 : P1 selected (burst 5)
Time 6 : P2 selected (burst 5)
Time 8 : P1 selected (burst 3)
Time 10 : P2 selected (burst 3)
Time 12 : P1 selected (burst 1)
Time 13 : P1 finished
Time 13 : P2 selected (burst 1)
Time 14 : P2 finished
Time 14 : Idle
Finished at time 15
P1 wait 5 turnaround 10
P2 wait 5 turnaround 14
Notes:
1. All integer numeric data is formatted using %3d.
2. Process names are specified in the input file.
3 Resources
There are many, many resources on Go available online. The list below should help you get quickly started.
• Basic building blocks: Go by example (Very useful for command line interfaces, files, and so much
more.
• A cookbook with examples: Go Language CookBook With Examples Nice seminar summary with
extensive examples and descriptions.
• What not to do: 50 Shades of Go: Traps, Gotchas, and Common Mistakes for New Golang Devs Hint:
If you are new to Go the information here will save you hours debugging your code.
There are many different links that were provided during lecture and are in the Intro to GO slide deck.
Note that the links above work in most Acrobat Readers - with one notable exception - the Webcourses
PDF reader in the browser. To take advantage of the links, download this assignment PDF and use Adobe’s
Acrobat reader.
3
4 Grading
Scoring will be based on the following rubric:
Table 2: Grading Rubric
Deduction Description
-100 Cannot compile on eustis
-100 Cannot read input file specified on command line
-100 Cannot write output file specified on command line
- 50 Produces no meaningful output
- 20 Fails to produce appropriate Round-Robin schedule
- 20 Fails to produce appropriate Shortest Job First
schedule
- 20 Fails to produce appropriate preemptive First-Come
First-Served schedule
- 20 Fails to produce appropriate schedule for more than
5 processes
5 Submission Instructions
The assignment shall be submitted via WebCourses. The only file submitted should be the pa1.go source
file.