CS 326: Operating Systems. Lecture 1

Transcription

1 CS 326: Operating Systems Lecture 1

2 Welcome to CS 326! Glad to have you all in class! Lecture Information: Time: T, Th 9:55 11:40am Lab: M 4:45 6:20pm Room: LS G12 Course website: 8/21/18 CS 326: Operating Systems 2

3 Staff Instructor: Matthew Malensek Office Hours: M, T, Th 3:30 4:30pm (or by appointment!) Research: distributed systems, big data TA: Marcus Chong Office Hours: T, Th 12:45 2:15pm TA: Rugved Mavidipalli Office Hours: TBA 8/21/18 CS 326: Operating Systems 3

4 Communication You ll receive a signup later today for Piazza to the instructor is fine too, but if your question could help others then please post on Piazza! All announcements will be posted on Piazza 8/21/18 CS 326: Operating Systems 4

5 Enrollment Status We currently have 30 students enrolled with several more on the waitlist If you re enrolled, great! If not, please make note of this on our Lab 0 assignment that we ll do today 8/21/18 CS 326: Operating Systems 5

6 Quick Note: Prerequisites CS 220 or CS 221 with a C or better CS 245 with a C or better 8/21/18 CS 326: Operating Systems 6

7 Today s Agenda Syllabus Our computing platform: the Raspberry Pi Introduction to Operating Systems 8/21/18 CS 326: Operating Systems 7

8 Today s Agenda Syllabus Our computing platform: the Raspberry Pi Introduction to Operating Systems 8/21/18 CS 326: Operating Systems 8

9 Staying up to Date Check the course website before class for: Syllabus Recent announcements Assignments Printable lecture notes Grades will be posted on Canvas Project submissions: GitHub 8/21/18 CS 326: Operating Systems 9

10 You Will Learn How to configure a Linux-based operating system and work from the shell Operating system components and implementations Threads, processes, synchronization, system calls, scheduling, virtual memory, and file systems How to develop UNIX system software, including concurrent programs Debugging complex systems and low-level software UNIX tools such as make and git 8/21/18 CS 326: Operating Systems 10

11 Books Operating Systems: Three Easy Pieces Remzi H. Arpaci-Dusseau and Andrea C. Arpaci- Dusseau Free online as a PDF. You can also buy a hard copy. The C Programming Language, 2nd Edition Brian W. Kernighan and Dennis M. Ritchie 8/21/18 CS 326: Operating Systems 11

12 Course Structure OS class is a bit unique: there s a decent amount of theory, but we ll get to apply it in practical situations We ll have small practice problems (homework/lab) as well as ~4 larger projects There s also a lab session on Mondays. Lab time gives you the opportunity to work on your homework/projects and get feedback right away We ll do interactive grading in the lab 8/21/18 CS 326: Operating Systems 12

13 Evaluation No midterm exams We ll have a quiz every 3 weeks; dates posted on the course schedule page Individual + Group component Final exam: not required If you don t do well on a quiz or miss one, then you can take the comprehensive final exam and replace up to two quiz scores 8/21/18 CS 326: Operating Systems 13

14 Grade Distribution Homework/Labs: 20% Quizzes: 30% Individual: 20% Group: 10% Projects: 50% 8/21/18 CS 326: Operating Systems 14

15 Grading Score Grade A A B B B C C C D D D F 8/21/18 CS 326: Operating Systems 15

16 Simplified Grading HW/Labs 10 A working solution. Functions are commented and code is formatted consistently. 9 A working solution with minor issues, or poor documentation/formatting. 5 Partial solution 0 Incorrect solution or no submission. 8/21/18 CS 326: Operating Systems 16

17 Policies Assignments are due at 11:59 pm on the due date Late homework/labs are not accepted Slip days: you get 4 slip days that you can use over the course of the semester Use them to turn in projects late, OR correct bugs in your graded project 8/21/18 CS 326: Operating Systems 17

18 Today s Agenda Syllabus Our computing platform: the Raspberry Pi Introduction to Operating Systems 8/21/18 CS 326: Operating Systems 18

19 Raspberry Pi Most of the work we ll be doing in class will be on the Raspberry Pi Specifically, the Raspberry Pi 3 Model B -or- Raspberry Pi 3 Model B+ Credit card sized singleboard computer Everyone will need to get a a Pi ~$36 + accessories 8/21/18 CS 326: Operating Systems 19

20 Pi Specs (Pi B 3+) 1.4GHz 64-bit quad-core ARMv8 CPU, 1 GB RAM n Wireless LAN, 10/100/1000Mbps LAN Bluetooth, 4 USB ports, 40 GPIO pins, Full HDMI port, Combined 3.5mm audio jack and composite video Camera interface (CSI), Display interface (DSI), VideoCore IV 3D graphics core 8/21/18 CS 326: Operating Systems 20

21 Why Pi? You ll get experience working with Linux without needing to virtualize or dual boot your laptop Freedom to break things: if you completely wipe out your OS, just reload it and start over The Pi is currently the de facto standard in single board computers Besides being a portable, simple platform for learning Operating Systems, the Pi is useful for tons of other applications! 8/21/18 CS 326: Operating Systems 21

22 Pi Compute Cluster 8/21/18 CS 326: Operating Systems 22

23 GPIO Pins The Pi General Purpose IO (GPIO) pins can be used to add external devices such as sensors 8/21/18 CS 326: Operating Systems 23

24 Other Uses Home web server Streaming music server Home automation Etc Order your components ASAP, we ll set up the software next Tuesday: (I ll put this link on the website -> schedule page) 8/21/18 CS 326: Operating Systems 24

25 Minimum Hardware Requirements A Raspberry Pi 3 Model B USB TTL cable A USB power cable (recommended: with a switch) An 8GB (or higher) micro SD card (get high speed) Optional: case Optional: USB Ethernet adapter 8/21/18 CS 326: Operating Systems 25

26 Make Your Life Easier Get a good power supply. Often students can t get their Pi to work because their laptop can t power it! Get a good SD card. There are cheap, counterfeit cards available but they: Aren t actually as big as they say they are Fail in a couple days Explode into a fiery inferno, causing death and destruction Treat your Pi with the love and respect it deserves J 8/21/18 CS 326: Operating Systems 26

27 Today s Agenda Syllabus Our computing platform: the Raspberry Pi Introduction to Operating Systems 8/21/18 CS 326: Operating Systems 27

28 Operating Systems 8/21/18 CS 326: Operating Systems 28

29 Operating System So, what is an OS? An OS provides a layer of abstraction between your computer s hardware and software Computer science is all about layers of abstraction: Nobody wants to program in binary, so we have assembly Nobody wants to program in assembly, so we have C Nobody wants to manage their own memory, so there s Java Nobody wants to write another AbstractFactoryBuilderPattern, so there s Python 8/21/18 CS 326: Operating Systems 29

30 Virtualization The basic concept of OS is Virtualization Rather than exposing the hardware directly to programs, a nice set of virtual interfaces are provided Logitech MX Mouse à Mouse Samsung 1 TB SSD à Mass storage device Etc. Programs don t have to worry about what s going on in the system Appear to have their own CPU, memory, etc 8/21/18 CS 326: Operating Systems 30

31 OS Diagram Nice, Friendly Layer No need for apps to worry about the hardware 8/21/18 CS 326: Operating Systems 31

32 Before Operating Systems To understand the role of the OS, it s easier to think about how things were before we had them In ye olden times, running a program meant putting a giant floppy disk in your computer and booting it up After boot, the program then had complete control over the computer Must interface with the hardware directly 8/21/18 CS 326: Operating Systems 32

33 8/21/18 CS 326: Operating Systems 33

34 Program Execution Once the boot process is complete, your program has total control over the system hardware Great! But How do we support all the different types of hardware out there? It would be nice to not reinvent the wheel (graphics routines, I/O, etc) every time we write a new program What about multitasking? We need an Operating System! 8/21/18 CS 326: Operating Systems 34

35 Primitive Processes Early PC operating systems such as DOS provided a process abstraction: Instantiated state of a program: code, data, etc. This allowed the OS to provide hardware abstraction and execute different types of programs Each process has full control of the hardware Only one process runs at a time Eventually, cooperative multitasking allowed programs to run at the same time 8/21/18 CS 326: Operating Systems 35

36 CPU Scheduling 8/21/18 CS 326: Operating Systems 36

37 Modern Processes Today, processes are scheduled preemptively The process state or context is saved and swapped out with another OS scheduler decides which processes get to run Processes are given their own virtual memory space Not allowed to interfere with other processes or the operating system Resource limits keep rogue/runaway processes in check 8/21/18 CS 326: Operating Systems 37

38 Security and Resource Mgmt Isolating programs from one another helps enforce security constraints OS generally have support for multiple concurrent users and permissions The OS is also in charge of allocating resources Assigning memory, CPU usage 8/21/18 CS 326: Operating Systems 38

39 OS Components An operating system is composed of several different parts The main component is the kernel The kernel controls everything Hardware, software, resource allocation, privileged operations Linux itself isn t an OS: it s actually a Kernel This why it s often called GNU+Linux (GNU User space) 8/21/18 CS 326: Operating Systems 39

40 Our Focus This course will cover two domains: User space most OS include lots of bundled programs. These really aren t that much different than the programs we write on a day-to-day basis Kernel space provides all the functionality that makes virtualizing the hardware possible Exposes an API to the user space: system calls And we ll write code for both 8/21/18 CS 326: Operating Systems 40

41 Wrapping Up Welcome to class (again!) Ask questions, come to instructor/ta office hours. We re here to make sure you succeed! Next class: We ll define what OS responsibilities are and look at some examples C Review Last thing: please fill this out 8/21/18 CS 326: Operating Systems 41