CS计算机代考程序代写 distributed system concurrency Excel single.dvi

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A Dialogue on the Book

Professor: Welcome to this book! It’s called Operating Systems in Three Easy
Pieces, and I am here to teach you the things you need to know about operating
systems. I am called “Professor”; who are you?

Student: Hi Professor! I am called “Student”, as you might have guessed. And
I am here and ready to learn!

Professor: Sounds good. Any questions?

Student: Sure! Why is it called “Three Easy Pieces”?

Professor: That’s an easy one. Well, you see, there are these great lectures on
Physics by Richard Feynman…

Student: Oh! The guy who wrote “Surely You’re Joking, Mr. Feynman”, right?
Great book! Is this going to be hilarious like that book was?

Professor: Um… well, no. That book was great, and I’m glad you’ve read it.
Hopefully this book is more like his notes on Physics. Some of the basics were
summed up in a book called “Six Easy Pieces”. He was talking about Physics;
we’re going to do Three Easy Pieces on the fine topic of Operating Systems. This
is appropriate, as Operating Systems are about half as hard as Physics.

Student: Well, I liked physics, so that is probably good. What are those pieces?

Professor: They are the three key ideas we’re going to learn about: virtualiza-
tion, concurrency, and persistence. In learning about these ideas, we’ll learn
all about how an operating system works, including how it decides what program
to run next on a CPU, how it handles memory overload in a virtual memory sys-
tem, how virtual machine monitors work, how to manage information on disks,
and even a little about how to build a distributed system that works when parts
have failed. That sort of stuff.

Student: I have no idea what you’re talking about, really.

Professor: Good! That means you are in the right class.

Student: I have another question: what’s the best way to learn this stuff?

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2 A DIALOGUE ON THE BOOK

Professor: Excellent query! Well, each person needs to figure this out on their
own, of course, but here is what I would do: go to class, to hear the professor
introduce the material. Then, at the end of every week, read these notes, to help
the ideas sink into your head a bit better. Of course, some time later (hint: before
the exam!), read the notes again to firm up your knowledge. Of course, your pro-
fessor will no doubt assign some homeworks and projects, so you should do those;
in particular, doing projects where you write real code to solve real problems is
the best way to put the ideas within these notes into action. As Confucius said…

Student: Oh, I know! ’I hear and I forget. I see and I remember. I do and I
understand.’ Or something like that.

Professor: (surprised) How did you know what I was going to say?!

Student: It seemed to follow. Also, I am a big fan of Confucius, and an even

bigger fan of Xunzi, who actually is a better source for this quote1.

Professor: (stunned) Well, I think we are going to get along just fine! Just fine
indeed.

Student: Professor – just one more question, if I may. What are these dialogues
for? I mean, isn’t this just supposed to be a book? Why not present the material
directly?

Professor: Ah, good question, good question! Well, I think it is sometimes
useful to pull yourself outside of a narrative and think a bit; these dialogues are
those times. So you and I are going to work together to make sense of all of these
pretty complex ideas. Are you up for it?

Student: So we have to think? Well, I’m up for that. I mean, what else do I have
to do anyhow? It’s not like I have much of a life outside of this book.

Professor: Me neither, sadly. So let’s get to work!

1According to http://www.barrypopik.com (on, December 19, 2012, entitled “Tell
me and I forget; teach me and I may remember; involve me and I will learn”) Confucian
philosopher Xunzi said “Not having heard something is not as good as having heard it; having
heard it is not as good as having seen it; having seen it is not as good as knowing it; knowing
it is not as good as putting it into practice.” Later on, the wisdom got attached to Confucius
for some reason. Thanks to Jiao Dong (Rutgers) for telling us!

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