William Stallings Computer Organization and Architecture

1
William Stallings Computer Organization and
Architecture

• Chapter 2Computer Evolution and Performance

2
2.1 A BRIEF HISTORY OF COMPUTERThe First
Generation Vacuum Tubes ENIAC - background

• Electronic Numerical Integrator And Computer
• Designed and constructed Under the supervision of
  Eckert and Mauchly at University of Pennsylvania
• Trajectory tables for weapons
• Started 1943
• Finished 1946
• Too late for war effort
• Used until 1955

3
ENIAC - details

• Decimal (not binary)
• 20 accumulators of 10 digits
• Its memory consisted of 20 accumulators, each
  capable of holding a 10-digit decimal number.
  Each digit was represented by a ring of 10 vacuum
  tubes.
• Programmed manually by switches
• 18,000 vacuum tubes
• 30 tons
• 15,000 square feet
• 140 kW power consumption
• 5,000 additions per second

4
ENIAC
5
The von Neumann/Turing

• Stored Program concept
• Main memory storing programs and data
• ALU operating on binary data
• Control unit interpreting instructions from
  memory and executing
• Input and output equipment operated by control
  unit
• Princeton Institute for Advanced Studies
• the IAS computer
• Completed 1952
• The IAS computer is the prototype of all
  subsequent general-purpose computer.

6
Structure of von Neumann machine
7
Structure of IAS detail
8
IAS - details

• 1000 x 40 bit words
• Binary number
• 2 x 20 bit instructions
• Each words can contain two instructions (p21
  Figure 2.2)
• 8-bit operation code specifying the operation to
  be performed and a 12-bit address designating one
  of the words in memory
• Set of registers (storage in CPU)
• Memory Buffer Register (MBR)
• Memory Address Register (MAR)
• Instruction Register (IR)
• Instruction Buffer Register (IBR) Employed to
  hold temporarily the right-hand instruction from
  a word in memory.
• Program Counter (PC)
• Accumulator (AC)
• Multiplier Quotient (MQ)
• The IAS computer had a total of 21 instructions
  (p24 Table 2.1).

9
Figure2.2 IAS Memory Format
Sign Bit
(b) Instruction Word
10
Commercial Computers

• 1947 - Eckert-Mauchly Computer Corporation
• UNIVAC I (Universal Automatic Computer)
• US Bureau of Census 1950 calculations
• Became part of Sperry-Rand Corporation
• Late 1950s - UNIVAC II
• Faster
• More memory

11
IBM

• Punched-card processing equipment
• 1953 - the 701
• IBMs first electronic stored-program computer
• Scientific calculations
• 1955 - the 702
• Business applications
• Lead to 700/7000 series

12
The Second Generation Transistors

• Replaced vacuum tubes
• Smaller
• Cheaper
• Less heat dissipation
• Solid State device
• Made from Silicon (Sand)
• Invented 1947 at Bell Labs
• William Shockley et al.

13
(No Transcript)
14
Transistor Based Computers

• Second generation machines
• NCR RCA produced small transistor machines
• IBM 7000
• DEC (Digital Equipment Corporation)- 1957
• Produced PDP-1

15
Generations of Computer

• Vacuum tube - 1946-1957
• Transistor - 1958-1964
• Small scale integration - 1965 on
• Up to 100 devices on a chip
• Medium scale integration - to 1971
• 100-3,000 devices on a chip
• Large scale integration - 1971-1977
• 3,000 - 100,000 devices on a chip
• Very large scale integration - 1978 to date
• 100,000 - 100,000,000 devices on a chip
• Ultra large scale integration
• Over 100,000,000 devices on a chip

16
Microelectronics

• Literally - small electronics
• A computer is made up of gates, memory cells and
  interconnections.
• A gate is a device that implements a simple
  Boolean or logical function. Gates are
  responsible for controlling data flow.
• The memory cell is a device that can be in one
  of two stable states, can store one bit of data.
• These can be manufactured on a semiconductor
• e.g. silicon wafer
• Figure 2.7 Relationship between Wafer, Chip and
  Gate

17
Moores Law

• Increased density of components on chip
• Gordon Moore - cofounder of Intel
• Number of transistors on a chip will double every
  year
• Since 1970s development has slowed a little
• Number of transistors doubles every 18 months
• Cost of a chip has remained almost unchanged
• Higher packing density means shorter electrical
  paths, giving higher performance
• Smaller size gives increased flexibility
• Reduced power and cooling requirements
• Fewer interconnections increases reliability

18
Growth in CPU Transistor Count
Figure2.8 Growth in CPU transistor Count
19
IBM 360 series

• 1964
• Replaced ( not compatible with) 7000 series
• First planned family of computers
• The characteristics of a family
• Similar or identical instruction sets
• Similar or identical OS
• Increasing speed
• Increasing number of I/O ports (i.e. more
  terminals)
• Increased memory size
• Increased cost
• Multiplexed switch structure

20
DEC PDP-8

• 1964
• First minicomputer
• Did not need air conditioned room
• Small enough to sit on a lab bench
• 16,000 (cheaper)
• 100k for IBM 360
• Embedded applications OEMs
• The PDP-8established the concept of
  minicomputers, leading the way to a multibillion
  dollar industry.
• BUS STRUCTURE

21
DEC - PDP-8 Bus Structure
I/O Module
Main Memory
I/O Module
Console Controller
CPU
OMNIBUS
Figure 2.9 PDP-8 Bus Structure The PDP-8 bus ,
called the omnibus, consists of 96 separate
signal paths, used to carry control, address, and
data signals.
22
Semiconductor Memory

• In 1970, Fairchild produced the first relatively
  capacious semiconductor memory.
• Size of a single core
• i.e. 1 bit of magnetic core storage
• Holds 256 bits
• Non-destructive read
• Much faster than core
• Capacity approximately doubles each year

23
Semiconductor Memory

• Since 1970, semiconductor memory has been through
  10 generations 1K, 4K, 16K, 64K, 256K, 1M, 4M,
  16M, 64M, and as of this writing, 256M bits on a
  single chip(1K210, 1M220).
• Each generation has provided four times the
  storage density of the previous generation,
  accompanied by declining cost per bit and
  declining access time.

24
Microprocessors

• Intel
• 1971- 4004
• First microprocessor
• All CPU components on a single chip
• The 4004 can add two 4-bit numbers and can
  multiply only by repeated addition.
• Followed in 1972 by 8008
• 8-bit microprocessor
• The 4004 and the 8008 both designed for specific
  applications
• 1974 - 8080
• Intels first general purpose microprocessor

25
2.2 DESIGNING FOR PERFORMANCE Microprocessor
Speed

• Pipelining
• On board cache
• On board L1 L2 cache
• Branch prediction
• predicts which branches, or groups of
  instructions, are likely to be processed next
• Prefetch the correct instruction and buffer them
  so that the processor is kept busy.
• Increase the amount of work available for the
  processor to execute.

26
Microprocessor Speed

• Data flow analysis
• Analyze the dependent relationship among the
  instructs.
• Create an optimized schedule of instruction
  independent of the original program order
• To prevent unnecessary delay.
• Speculative execution(????)
• Using branch prediction and data flow analysis
• Execute instructions ahead of their actual
  appearance
• To keep processor busy

27
Performance Mismatch

• Processor speed increased
• Memory capacity increased
• Memory speed lags behind processor speed

28
DRAM and Processor Characteristics
29
Trends in DRAM use
The shaded bands for a particular type of system
Solid black lines for a fixed-size memory
30
Solutions

• Increase number of bits retrieved at one time
• Make DRAM wider rather than deeper and by
  using wide bus data paths
• Change DRAM interface
• a cache or other buffering scheme on the DRAM
  chip
• Reduce frequency of memory access
• More complex cache and cache on chip
• Increase interconnection bandwidth
• High speed buses
• Hierarchy of buses

31
Pentium Evolution (1)

• 8080
• first general purpose microprocessor
• 8 bit data path
• Used in first personal computer Altair
• 8086
• much more powerful
• 16 bit
• instruction cache, prefetch few instructions
• 8088 (8 bit external bus) used in first IBM PC
• 80286
• 16 Mbyte memory addressable
• 80386
• 32 bit
• Support for multitasking

32
Pentium Evolution (2)

• 80486
• sophisticated powerful cache and instruction
  pipelining
• built in maths co-processor
• Pentium
• Superscalar
• Multiple instructions executed in parallel
• Pentium Pro
• Increased superscalar organization
• Aggressive register renaming
• branch prediction
• data flow analysis
• speculative execution

33
Pentium Evolution (3)

• Pentium II
• MMX(????????) technology
• graphics, video audio processing
• Pentium III
• Additional floating point instructions for 3D
  graphics
• Pentium 4
• Note Arabic rather than Roman numerals
• Further floating point and multimedia
  enhancements
• Itanium
• 64 bit
• see chapter 15
• See Intel web pages for detailed information on
  processors

34
Internet Resources

• http//www.intel.com/
• Search for the Intel Museum
• http//www.ibm.com
• http//www.dec.com
• Charles Babbage Institute
• PowerPC
• Intel Developer Home