20190716

1. Computer Abstractions and Technology 

1.1 Introduction

1.2 Eight Great Ideas in computer

1.3 Below Your Program

1.4 Under the Covers

1.5 Technologies for Building Processors and memory

1.6 Performance

1.7 The power Wall 

1.8 The Sea change: The Switch from Uniprocess to Multiprocessors

1.9 Real stuff : Benchmarking the Intel Core i7

1.10 Fallacies and Pitfalls

1.11 Concluding Remarks 

1.12 Historical Perspective and Futher Reading 

1.13 Exercises 

Cicilization advances  by extending the number of important operations which we can perform without thinking about them.      

Alfred North Whitehead, 

An Introduction to Mathematics, 1911 

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1. abstraction/ / n. a general idea about a type of situation, thing, or person, rather than a specific example from real life 抽象概念  }

 

 

1.1 Introduction

Welcome to this book! We're delighted to have this opportunity to convey the excitement of the world of computer systems. This is not a dry and dreary field, where progress is glacial and where new ideas atrophy from neglect. No! Computers are the product of the incredibly vibrant information technology industry, all aspects of which are responsible for almost 10% of the gross national product of the United States, and whoes economy has become dependent in part on the rapid improvements in information technology promised by Moore's Law. This unusual industry embraces innovation at a breath-taking rate. In the last 30 years, there have been a number of new computers whose introduction appeared to revolutionize the computing industry; these revolutions were cut short only because someone else built an even better computer.

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1. delighted / / adj. very pleased and happy. 愉快的， 高兴的  be delighted to do sth.

2. convey// v. to communicate information or a message 传递、传送

3. excitement //n. the feeling of being excited. 兴奋、激动 the excitement of...

4.gross // adj. = total = a gross amount of mpney is the total amount before any tax or costs have been away (扣去锐或成本之前)总的、毛的

gross national product. n [sigular] technical the GNP, the total value of all the goods and services produced in a country, including income from aborad[术语]国民生产总值

5.economy // n. the system by which a country's money and goods are produced and used, or a country considered in this way. 经济、经济情况、经济制度

6. vibrant // adj.exciting and full of activity enery 令人兴奋的，充满活力的，精力充沛的，活跃 的

7.Incredibly // adv. = extremely 极端的，难以置信的

8.revolutionize// v. to completely change the way people think or do things, especially becauseof a new idea or invention 使彻底变革

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　　This race to innovate has led to unprecedented progress since the inception of electronic computing in the 1940s. Had the transportation industry kept pace with the computer industry,for example, today we could travel from New York to london in a second for a penny. Take just a moment to contemplate how such an improvement would change society--- living in tahiti while working in San Francision, going to Moscow for an eveningayt at the bolshoiBallet--- and you can appreciate the implcations of such a change .

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1.unprecedented // adj. never having happened before, or never having happened so much.空前的，前所未有的

2. inception// n. [singular] formal the start of an organization or institution [正式]{组织或机构的}开创；开端；

3.innovate // v. to start to use new idea, method or invention. 革新， 创新， 改革

4. contemplate// v. to think about something that you intend to do in the future.打算，想，考虑；

5.race// n. 竞赛；

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　　Computers have led to a third revolution for civilization, with the information revolution taking its place alongside the agricultural and industrial revolutions. The resulting multiplication of humankind's intellectual strength and reach naturally has affected our everyday lives profoundly and changed the ways in which the search for new knowledge is carried out. There is now a new vein of scientific investigation, with computational scientists joining theoretical and experimental scientists in the exploration of new frontiers in astronomy, biology, chemistry, and physics, among others.

　　The computer revolution continues. Each time the cost of computing improves by another factor of 10, theopportunities for computers multiply. Applications that were economically infeasible suddenly become practical. In the recent past, the following applications were "computer science fiction."

• 　　Computers in automobies:Until microprocessors improved dramatically in price

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