Reading as a god

Chapter 199 I Have a Laboratory
The book "Computer Systems: A Programmer's Perspective" covers a wide range of topics, and Zhang Shan believes that it is not necessary to read it word for word.

According to Zhang Shan's personal point of view, we should focus on reading Chapter 1 "A Tour of Computer Systems" and the first part "Program Structure and Execution" (starting from Chapter 2, which occupies about half of the book), which contains After knowing the machine-level representation of data, assembly language and execution methods, and CPU architecture, we should critically understand its principles.

For example, Chapter 6 "Optimizing Program Performance" proposes many machine-level optimization methods. It seems that some of them are too detailed, and are no longer recommended in the actual work process (such as inlining some methods to Improve performance), we must grasp the "why" instead of simply absorbing the "how".The second part of the book "Running Programs on a System" mainly talks about the content of the operating system, which can be read a little easier, but Chapter 10 "Virtual Memory", which talks about virtual memory in the operating system All aspects of the mechanism are critical and need to be read carefully.As for the third part of the book, "Interaction and Communication Between Programs", you can read it more "selectively". Zhang Shan only read Chapter 13 "Concurrent Programming", and simply scanned the other two chapters.

As a classic textbook, it must have many additional resources. For example, some links are given on its official site, the most important of which may be the learner site, which includes various tools needed for this book, reference documents, etc. resource.

In the process of reading, Zhang Shan remembered that a certain big cow mentioned two books before, one is a domestic excellent book "Link, Loading and Library".

This book mainly explains the process of "generating files" in the compilation process, and how files are loaded by the operating system when the application is executed, and it involves both Linux and Windows platforms.

The second book is "Windows Internals 5th Edition", and People's Posts and Telecommunications Publishing House has introduced its photocopy version.

Compared with the "can't get in" book Zhang Shan is reading now, this is indeed a "deep" level book.

It basically covers all aspects of the Windows kernel, including system architecture, memory management, thread scheduling, security mechanisms, file systems and other topics. For our programmers on the Windows platform, this content may be more targeted.

Zhang Shan just bought this book not long ago, let alone read it carefully.

Of course, the so-called purchase of books was naturally ordered by Luo Changhui~
Now Zhang Shan doesn’t pay much attention to this kind of trivial matter, although Zhang Shan earns every minute of reading~
There is no way to count whether it is good or not, except for the income from studying for a long time, Zhang Shan doesn't care about the money at all~
With Zhang Shan's current life, even without making any changes.

The money in the bank every day will also bring a lot of interest, and even if you don't spend the money deliberately, the daily turnover is scary...

Zhang Shan noticed that this book and "C Expert Programming" are similar in some places~
~~~
Zhang Shan noticed the anecdote mentioned in the book he was reading now.

"The 20s were the era of large, complex operating systems such as IBM's OS/60 and Honeywell's Multics system. OS/360 was one of the most successful software projects in history, while Multics persisted for many years. , but has never been widely used. Bell Labs was an initial participant in the Multics project, but withdrew in 360 because of the complexity and lack of progress of the project. In view of the unpleasant experience of the Mutics project, a group of Bell Labs The researchers at the time -- Ken Thompson, Dennis Ritchie, Doug Mellroy, and Joe Ossanna -- wrote a much simpler operating system entirely in machine language on the DEC PDP-1969 computer starting in 1969. Many of the new systems Ideas, such as the hierarchical file system and the concept of the shell as a user-level process, all come from Multics, but are implemented in a smaller, simpler package. In 7, Brian Kernighan named the new system "Unix", which Also a pun, alluding to the complexity of "Multics". In 1970, its kernel was rewritten in C, and in 1973, Unix began to be officially released.

Bell Labs provided the source code to schools on generous terms, so Unix received a lot of support and continued development in colleges and universities.The most influential work occurred in the late 20s and early 70s. At the University of California, Berkeley, researchers added virtual memory and Internet protocols to a series of releases, called Unix80.xBSD (Berkeley Software Distribution) .At the same time, Bell Experiments announced that it was releasing its own version, called SystemVUnix.Other vendors' versions, such as Sun Microsystems' Solaris system, are derived from these original BSD and System V versions.

Trouble ensued in the mid-20s when the Unix vendors tried to differentiate their programs by adding broken and often incompatible features.In order to stop this trend, IEEE (Institute of Electrical and Electronics Engineers) began to work hard to standardize the development of Unix, which was later named "Posix" by Richard Stallman.The result was a family of standards, called Posix standards.This set of standards covers many aspects, such as the C language interface of Unix system calls, shell programs and tools, threads and network programming.More recently, an independent standardization effort known as the "Standard Unix Specification" has joined with Posix to create a unified Unix system standard.As a result of these standardization efforts, the differences between Unix versions have largely disappeared"

Zhang Shan keenly noticed that the two books seemed to mention a common thing - Bell Labs~
On January 1925, 1, Walter Gifford, president of AT&T at the time, acquired the research department of Western Electronics Corporation and established an independent entity called "Bell Telephone Laboratories Corporation", which was later renamed Bell Laboratories. AT&T and Western Electronics each own 1 percent of the company.In the 50s, Bell Labs researchers introduced long-distance television transmission and digital computers, and led the development of talking movies and artificial larynx.Two important inventions of the information age - the transistor and information theory were both developed by Bell Laboratories in the 30s.Bell Labs' major inventions in the 40s and 50s included solar cells, the theory of lasers, and communication satellites.

As of today, Bell Labs has obtained more than 5000 patents, and now, on average, it obtains more than three patents every working day.Bell Labs' mission is to create, produce and deliver to customers innovative technologies that enable Lucent Technologies to be a global leader in communications systems, products, components and network software.A total of 8 (13 people) Nobel Prizes were won (including 7 physics prizes and 1 chemistry prize).

Is it just so rigid in any laboratory?

Zhang Shan felt that it was necessary for him to build a laboratory, although it could not be as high-end as Iron Man.

But a simple laboratory that can realize ideas is still of great practical significance.

Although Zhang Shan has never engaged in similar work, but these are not important.

He has superpowers after all!
In addition to emotion, Zhang Shan made the settlement in the system in time:
Speaking of which, although Zhang Shan reads very quickly, it still took him 3 hours to finish this book!

"Ding~ The host studied for 3 hour in total, gained a total of 21600 yuan in money, and a total of 43200 experience points (including the bonus of the No. [-] badge)"

"In addition, the host read a total of 50 words and earned a total of 50 US dollars~"

"The current system level is level 12, and the experience required to upgrade is 7/140"

Zhang Shan didn't get 50 all of a sudden, Zhang Shan was no longer as surprised as before.

The reason for getting US dollars is naturally because of system benefits~
Zhang Shan remembered the description of the system at that time:
"Every 5th level of the system is a small stage, and every 10th level is a big stage.

After the system level reaches level 11, it means that the system has entered a brand new stage - 2.0 stage.

At this stage, the system grants the host two additional benefits:
[-]. Every time the host reads a book with n million words (a book refers to a book in a broad sense, the content is limited to the first reading), in addition to the normal accumulated reading experience and money, an additional currency of n ten thousand yuan in the language of the book content~
[-]. Every time the host produces a book of n million characters (a book refers to a book in a narrow sense, it only refers to a paper book that has obtained a book number and is officially released; and the author must only write the book by himself, and cannot rely on the power and system of others), except In addition to the reading experience and money accumulated in the process of writing the book, you will get an additional currency of n million yuan corresponding to the language of the book content

These two benefits will take effect throughout the process of the system 2.0 stage, that is, the system from level 11 to level 20.

According to this rule, the books Zhang Shan reads are in English, and the currency he gets is naturally US dollars or British pounds.

And because the author of this book is a genuine American.

The money Zhang Shan harvested was naturally in US dollars.

Speaking of which, the author of this book is Randal E. Bryant, but he is a big figure in the computer industry.

In 1981, he received a Ph.D. in computer science from the Massachusetts Institute of Technology. He is currently the dean of the School of Computer Science at Carnegie Mellon University in the United States. He is a double fellow of ACM and IEEE, and has won awards from these two associations many times.

Professor Bryant has been teaching computer systems for more than 20 years. Combining his years of teaching experience in computer architecture courses, he began to shift his focus from how to design computers to how to enable programmers to better understand the system. More efficient, more reliable procedures are coming.

These are all bonuses. Speaking of which, Randal E. Bryant's most dazzling identity is a double member of ACM and IEEE.

ACM (Association for Computing Machinery) Chinese: International Computer Society. ACM is a worldwide professional organization for computer practitioners. Founded in 1947, it is the world's first scientific and educational computer society. It has more than 130 members in more than 10 countries and regions around the world. ACM is the most influential professional academic organization in the computer field in the world. The ACM Turing Award (AM Turing Award) is recognized as the world's Nobel Prize in the field of computing.The current chairman is Professor Vicki L. Hanson.

It is the world's largest professional academic organization in the computer field, bringing together international computer educators, researchers, industry professionals and students.The interest group also holds worldwide lectures and talks every year around the world (but mainly in the United States) for members to share their research results. ACM takes a strong organizational structure, extremely high technical specifications, and recognition of technological innovation as its important development criteria.

ACM has more than 100 members worldwide, covering industry, academia, and government agencies.

The development purpose of ACM is to devote itself to the scientific and professional development of computer science. The ACM society realizes its development purpose through conferences, journals, educational programs and special interest groups. ACM hosts more than 170 academic conferences each year and includes more than 50 academic journals.The included papers bring together the cutting-edge research and innovative thinking of the world's scientific research elites.

Although ACM is very famous, IEEE is also famous.

IEEE is the Institute of Electrical and Electronics Engineers.

It is an international association of electronic technology and information science engineers. It is currently the world's largest non-profit professional technical society, with more than 40 members in more than 160 countries.

IEEE is committed to the development and research of electrical, electronic, computer engineering and science-related fields. It has formulated more than 900 industry standards in the fields of space, computer, telecommunications, biomedicine, power and consumer electronics, and has now developed Become an international academic organization with greater influence.At present, 28 colleges and universities in BJ, Shanghai, Xi'an, Zhengzhou, Jinan and other places have established IEEE student chapters.

No matter which one is not a vegetarian, the strength of Randal E. Bryant can be seen from this.

However, these things have nothing to do with Zhang Shan!
Zhang Shan, who has gained a lot of experience and money again, is a little excited on the surface, but she is as stable as an old dog in her heart~
50 is nothing~
After all, he is a man with ten digits in his bank card.

With a lot of money, it is natural to go shopping. Zhang Shan didn't think of daily life, but thought of the system mall first.

Thinking of meeting two foreign girls recently, Zhang Shan remembered the regularity of item cards.

Then I opened the system mall, and saw those four in the list of the mall.

"Still Enjoy Reading Card": 1 point coupon;
"Miaoxiang Reading Card": a coupon of 5 points;
"Enjoy reading card": 10 point coupons;
"Preferential reading card": 20 point coupons;
(Note: At present, cards of the same type can be stacked, and different cards are not allowed to be stacked)

And there is no more than a new card prop card.

Zhang Shan couldn't help feeling tangled in her heart, is it because these two are foreign girls this time?
Or is it because the time is relatively short and the unlocking condition has not been triggered yet?

System: Ahem, the host refreshes up to four item cards in a single natural month.

Zhang Shan? ? ?

Good guy, isn't this a waste of two objects that can refresh new props?

If I had known earlier, I would have taken the two sister papers down after a while~
system. . .

But one thing to say, the current system's prop card functions are basically complete.

The functions and usage methods of Zhang Shanji's various prop cards.

"Still Enjoy Reading Card": 1 point coupon

(Using this card, the host can enter the meson space and read for one hour. It can be used in combination. If the host stays in the meson space for one hour, the time in the host's normal world will only pass by one picosecond.

Note: The host of this card can only be used for reading. When using this card, the rules for the host to gain experience from reading books are the same as the rules for the host to gain experience in the real space. When using this card, the host cannot get any money.

In particular, the host needs to meditate for 30 minutes before and after using this card to avoid unknown risks caused by the different time rules in meson space and real space. )
关于一皮秒，章杉知道1皮秒=1000000渺秒，1 皮秒=1000飞秒；1皮秒等于一万亿分之一（即10的负12次方）秒。

That is to say, when using the "Still Reading Card", it is basically equivalent to the fact that the flow of time in the real world is static.

(End of this chapter)