COMS W4118 Operating Systems I

Spring 2025 Course Overview

• TR 4:10pm-5:25pm, 309 Havemeyer Hall

• Two synchronous and in-person exams for all sections:
  • Exam 1: 3/13 4:10pm
  • Exam 2: 5/13 4:10pm

  All students in all sections MUST take the exams at those times. There are no make-up or alternate exams. If you cannot make any of those exams, please take the course next semester.

• Instructor: Kostis Kaffes
• Office hours: Calendar
• REQUIRED READING: ACADEMIC HONESTY POLICIES
• 4118 Dev Guides

HW Due Dates

Date	Assignment
F 1/24	HW0 due
Su 2/2	HW1 due
M 2/17	HW2 due
Th 2/27	HW3 due
Su 3/14 3/23	HW4 due
F 4/11	HW5 due
TBD	HW6 due
TBD	HW7 due

Course Schedule

1/21

Course overview and logistics

• Lecture:
  • L01-overview

• Assignments:

  1. Check that you have access to Ed

  2. Read the following two documents:
     • http://www.cs.columbia.edu/education/honesty
     • http://www.cs.columbia.edu/~jae/honesty.html

  3. HW0 (individual assignment) – due Fri 1/24, 11:59pm

     Send an email to Kostis containing:

     • To: kkaffes@cs.columbia.edu
     • Subject: “[4118] hw0-UNI” – without quotes, sole space before hw0, UNI replaced with your actual UNI in lowercase
     • Your name, major & school program, year – ex) Kostis Kaffes, Electrical and Computer Engineering, National Technical University of Athens, class of 2015
     • Your pledge – see http://www.cs.columbia.edu/~jae/honesty.html
     • CS classes taken and/or other programming background
     • Optionally anything else you want to let me know
     • Optionally attach a picture of you, but please reduce image file size to about 100KB
  4. Start forming your group of three people

1/23

Introduction to OS/Unix

• Lecture:
  • L02-introduction
  • Code
• Reading:
  • APUE: chapter 1, 2.3, 2.4
  • OSTEP: chapter 2
  • LKD: chapter 1

HW1: linux-list

• Individual assignment, due Sunday 2/2
  • linux-list

1/28

Linux Overview

• Lecture:
  • L03-Linux
  • Code

1/30

UNIX signals

• Lecture:
  • L04-unix-signals
  • Code
• Reading:
  • APUE 9.4 - 9.6: skim, just to get a sense of process group, session, and controlling terminal
  • APUE 9.7: skim pages 299-301, skip rest – just to get a sense of jobs running in foreground and background
  • APUE 10.1 - 10.6 (skim signal descriptions in 10.2)
  • APUE 10.8 - 10.9
  • APUE 10.10: you can skip pages 340-341 & 343 (but interesting read if you know setjmp() / longjmp() or willing to find out)
  • APUE 10.11 - 10.13
  • APUE 10.14: skip page pages 352-353

UNIX File I/O

• Lecture:
  • L04-unix-io
  • Code
• Reading:
  • APUE: 3.1-3.13
  • APUE: 8.1-8.10
  • APUE chapter 5 (skim)

HW2: shell

• Individual assignment, due Monday 2/17
  • shell

2/4

Interprocess communication in UNIX

• Lecture:
  • L05-unix-ipc
  • Code
• Reading:
  • APUE 15.2, 15.5
  • APUE 15.10
    • APUE 15.8 (just pgs 565-566): semaphore semantics
  • APUE 7.6 - 7.7
  • APUE 7.8: a little bit off-topic, so optional
  • APUE 14.8: read page 525-527, skim the rest
  • APUE 15.9: page 576-578

POSIX threads

• Lecture:
  • L05-threads
  • Source code
• Reading:
  • APUE 11.1 - 11.4
  • APUE 11.5: read page 388-393; skip the rest of 11.5
  • APUE 11.6: read up to (and including) 11.6.6

2/6

Nonblocking I/O and I/O multiplexing

• Reading:
  • APUE 14.2
  • APUE 14.4.0 (i.e., page 500-501)
  • APUE 14.4.1
  • epoll
• Lecture:
  • L06-advanced-io

UNIX domain sockets

• Reading:
  • APUE 17.1
  • APUE 17.2: pages 631-633 are optional, but recommended
  • APUE 17.2.1
  • APUE 17.3: pages 637-641 are optional, but recommended
  • APUE 17.4: read 642-643, skip the rest
• Lecture:
  • L06-dom-sock
  • Source code

2/11

Linux System Calls

• Reading:
  • OSTEP chapter 4 (previously assigned)
  • OSTEP chapter 6 (previously assigned)
  • LKD chapter 2
  • LKD chapter 3: skim pages 37-40
  • LKD chapter 5
• Lecture:
  • L07-syscalls
  • Source code

2/13

Run queues and wait queues

• Reading
  • Process states (previously assigned)
    • OSTEP 4.4
    • LKD pages 27-28
  • Scheduling basics & wait queues
    • LKD pages 57-61
• Lecture
  • L08-run-wait-queues

2/18

Interrupts & Spin Locks

• Reading:
  • Interrupts: LKD chapter 7
  • Kernel locks: LKD chapter 10: pages 183 (from Spin Locks) - 202
  • Preemption: LKD pages 62 - 64 (before Real-Time Scheduling Policies)
• Lecture:
  • L9-interrupts-spinlocks

HW3: tabletop

• Individual assignment, due Thursday 2/27
  • tabletop

2/20

Synchronization

• Reading:
  • OSTEP chapter 28 (sections 28.9, 28.10, 28.11, and 28.15 are optional)
  • Optionally, OSTEP chapter 30
  • OSTEP chapter 31
  • Optionally, read java.lang.Object API doc about wait(), notify(), notifyAll() if you haven’t already
• Lecture:
  • L10-sync-1
  • L10-sync-2

2/25

Synchronization (cont.)

2/27

Scheduling Algorithms

• Reading:
  • OSTEP chapters 7, 8
• Lecture:
  • L12-sched-algo

HW4: fridge

• Group assignment, due Sunday 3/23
  • fridge

3/4

Scheduling in Linux

• Reading:
  • OSTEP chapters 9, 10
  • LKD chapter 4:
    • pages 42 (Linux’s Process Scheduler) - 50
    • optional, but recommended: pages 50 - 56
    • pages 57 - 64: previously assigned, but read again
    • pages 64 - 67
• Lecture:
  • L13-sched-linux

3/6

Midterm Review

3/11

No class

3/13

Midterm

3/18

No class – Spring Break

3/20

No class – Spring Break

3/25

Memory Management Fundamentals

• Reading:
  • Address translation basics: OSTEP chapter 15
  • Segmentation: OSTEP chapter 16
    • see this blog if you want to learn about x86 segmentation (optional)
  • Free-space management: OSTEP chapter 17
  • Paging: OSTEP chapter 18
• Lecture:
  • L14-paging

HW5: Freezer

• Group assignment, due Friday 4/11
  • freezer

3/27

x86 Memory Management

• Reading:
  • Multi-level page table: OSTEP 20.3
  • Inverted page table: OSTEP 20.4
  • TLB: OSTEP 19
• Lecture:
  • L15-x86-mm

4/1

Virtual Memory Beyond Physical Memory

• Reading:
  • OSTEP chapter 21
  • OSTEP chapter 22
• Lecture:
  • L16-virt-mem

4/3

Memory Management in Linux

• Lecture:
  • L17-linux-mm

4/8

TBD

4/10

TBD

4/15

TBD

4/17

TBD

4/22

No class

4/24

TBD

4/29

TBD

5/1

Wrap-up and Final Review