Outline

• Introduction of Nachos
• Installation of Nachos
• Project 1 – Thread Management
• Report & Policy
• Presentation Details

Introduction of Nachos

What Is Nachos?

• Designed by Thomas Anderson at UC Berkeley in 1992
• Written in C++, has JAVA version
  • We use the C++ version here
• Educational OS that some components can be implemented by users
  • Process management
  • CPU scheduling
  • Memory management
  • File system management
  • Networking

What Is Nachos? (Cont.)

• Nachos is just a UNIX process runs on real OS
• Nachos uses simple MIPS R2/3000 instructions
• Turn program to MIPS binary code

Installation of Nachos

Linux only …

Linux Machine Only

• Theoretically, You can use any Linux distribution as your platform

  • Ubuntu, Fedora, Debian…
  • Remember to use 32-bit instead of 64-bit
    • Nachos4.0 said to support 64-bits but not been completely tested

• Recommended choice:

  • 32-bit Ubuntu 14.04

Environment

NachOS Software Structure

Download & Install VirtualBox

• Oracle VM VirtualBox
  • https://www.virtualbox.org/
• Download 32-bit Ubuntu 14.04
  • http://releases.ubuntu.com/14.04/

Setup

Install g++ and csh

sudo apt-get install g++
sudo apt-get install csh
sudo apt-get install make

Download NachOS & Cross Compiler

wget -d http://cc.ee.ntu.edu.tw/~farn/courses/OS/OS2015/projects/project.1/nachos-4.0.tar.gz
wget -d http://cc.ee.ntu.edu.tw/~farn/courses/OS/OS2015/projects/project.1/mips-x86.linux-xgcc.tar.gz

Install NachOS

untar nachos-4.0.tar.gz

tar -xvf nachos-4.0.tar.gz

move mips-x86.linux-xgcc.tar.gz to root and untar

sudo mv mips-x86.linux-xgcc.tar.gz /
cd /
sudo tar -zxvf mips-x86.linux-xgcc.tar.gz

Install NachOS (Cont.)

Change Directory of Cross Compiler

editing file "~/nachos-4.0/code/test/Makefile"

...
GCCDIR = /mips-x86.linux-xgcc/
...
CPP = /mips-x86.linux-xgcc/cpp0
...
CFLAGS = -G 0 -c $(INCDIR) -B/mips-x86.linux-xgcc/
...

Install NachOS (Cont.)

Make NachOS-4.0

cd ~/nachos-4.0/code
make

Test

cd ./userprog
./nachos -e ../test/test1

Total threads number is 1
Thread ../test/test1 is executing.
Print integer:9
Print integer:8
Print integer:7
Print integer:6
return value:0

Project 1

Thread Management

Issue to be solved…

./nachos -e ../test/test1 -e ../test/test2

Total threads number is 2
Thread ../test/test1 is executing.
Thread ../test/test2 is executing.
Print integer:9
Print integer:8
Print integer:7
Print integer:20
Print integer:21
Print integer:22
Print integer:23
Print integer:24
Print integer:6
Print integer:7
...

Report & Policy

Report contents, grading policy, late policy

Report

1. Motivation
   • Motivation and the problem analysis
   • What’s your plan to deal with the problem
2. Implementation
   • How do you implement to solve the problem in Nachos
   • You can including some (not all) important code segments and comments
3. Result
   • Experiment result and some discussion
   • Extra effort or observation

Submission

Create a folder for the source code and report

{Student ID}_Nachos1/
  |_ nachos-4.0/
  |_ report.pdf

// Name the folder w/o curly braces, e.g. r07943154_Nachos1

Compress

tar -zcvf {Student ID}_Nachos1.tar.gz ./{Student ID}_Nachos1

Your source code and report should be handed out by Ceiba

Grading Policy

• Nachos source code: (40%)
• Report: (40%)
• Correct format: (20%)
• No plagiarism

Late Policy

• 10% penalty per day
• After 7 days, you will get 70% penalty, but no more penalty after that.

Some tips for Nachos

• Design before coding.
  • Better create your own test program to get the idea.
• Trace before coding.
  • Some IDE or text editor is useful if you are not a professional vim/emac user.
• Google is your best friend.

Reference

• General Nachos Documentation
• Wiki - Not Another Completely Heuristic Operating System
• A Road Map Through Nachos
• University of Pittsburgh - NachOS

Presentation Details

• What’s your contribution to this project.
• Not necessary to make PPT.
  • You can just use your report and source code to present.
• The main point is…
  • Problem analysis and what’s you plan to solve it.
  • What you do with this project.
  • Extra observation.

tags: Fall 2020 OS