第1章计算机系统概述.ppt

有的书上称第四代是VLSI，从80年代开始（如本书和Andraw编的《结构化计算机组成》），有的书称第四代是LSI，从72年开始，有的又分成LSI时代和VLSI时代。 Ingot ? wafer ? die ? chip Please click “how chips are made” on the course website to see the steps in details. Question asked by a student: why is the wafer a round shape, not a square shape? Merits of Abstraction: easy understanding, easy designing, compatibility Difference between Architecture and Organization. Computer Architecture: 1)how the software looks at the hardware? 2) functional, abstract view of hardware reflected in software. 每一层用户看到的计算机是不一样的。最终用户工作在应用程序层面，看到的是应用程序虚拟机，只知道如何使用相应的应用程序；应用程序开发人员在程序设计语言层面工作，看到的是高级语言虚拟机，只要会使用各种程序设计语言编程；系统维护人员工作在操作系统层面，看到的是操作系统虚拟机，只要知道系统中的命令和工具如何使用；系统程序员（OS和编译器开发人员）工作在计算机逻辑结构层面，看到的是汇编语言虚拟机；而汇编语言就是一台计算机指令系统的符号化表示，计算机的功能和性能就由机器的指令系统集中体现出来。 Hello程序被启动后，计算机的动作过程如下： Shell程序读取字符串“./hello”中各字符到寄存器，然后存放到主存； “Enter”键输入后，操作系统内核（载入程序）根据主存中的字符串“hello”到磁盘上找到特定的hello目标文件，将其包含的指令代码和数据（“hello, world\n”）从磁盘读到主存，并将控制权转交给hello程序，即将hello程序的第一条指令的地址送到PC中；处理器从hello主程序的指令代码开始执行；Hello程序将“hello, world\n”串中的字节从主存读到寄存器，再从寄存器输出到显示器上。 Ingot ? wafer ? die ? chip Please click “how chips are made” on the course website to see the steps in details. Question asked by a student: why is the wafer a round shape, not a square shape? This slide gives some formulae to calculate the die cost. “X is n times faster than Y” in English means X = (n+1) Y. Need to explain 1) clock cycle, 2) clock frequency. Mention that CPI is important. So CPU time is determined by 3 factors. The formula is specially useful because it separates the 3 key factors that affect performance. Time : ( length, CPI, Clock). Which are software dependent and which are hardware dependent? The table shows how such 3 factors are affected by other techniques. So CPU time is determined by 3 factors. The formula is specially useful because it separates the 3 key factors that affect performance. Time : ( length, CPI, Clock). Which are software dependent and which are hardware dependent? The table shows how such 3