Jan 18, 2018
Morgan Kaufmann Publishers
April 27, 2017 January 25, 2016 Shambhu Upadhyaya
(www.cse.buffalo.edu/faculty/shambhu) lecture slides: Chapter 1
Computer Abstractions and Technology
Copyright/Acknowledgments
Morgan Kaufmann Publishers April 27, 2017 Copyright/Acknowledgments
The lecture material for this course has been adapted in part from
UC Berkeley, Penn State, Publisher andPrevious Semesters of
Offerings at UB Chapter 1 Computer Abstractions and Technology
Morgan Kaufmann Publishers
April 27, 2017 Overview Administrative Matters (5 minutes) Course
Style, Philosophy and Structure (15 min) Intro to Computer
Architecture (30 minutes) Chapter 1 Computer Abstractions and
Technology 3 Chapter 1 Computer Abstractions and Technology Course
Administration
Instructor:Shambhu Upadhyaya Davis Hall Office Hours: Tuesdays 9:30
am 11:00 am TAs:Hayreddin Ceker and Aleksey Charapko
Labs:UNIX/Linux accounts for all More info. will be provided later
Materials: Newsgroup:sunyab.cse.341 (may not use)
Blackboard:UBlearns Text:Computer Organization and Design: The
Hardware/Software Interface, Fifth Edition, Patterson and Hennessy
Chapter 1 Computer Abstractions and Technology 4 Textbook purchase
options
Paperback or eBook University Bookstore on campus New, used, rental
Greeks and Sneaks Bookstore, 2 blocks from UB South campus (on Main
street) Patterson Computer Org & Design, 5th Edition Amazon
Chapter 1 Computer Abstractions and Technology 5 Course Exams
Reduce the pressure of taking exams
Midterms: Friday Feb 26th, Friday March 25th, Monday May 2nd 50
minutes to take45 minute test ( in class) Our goal: test knowledge
vs. speed writing All mid-terms closed book, no cheat sheets
Necessary sheets will be provided No final exam Chapter 1 Computer
Abstractions and Technology 6 Course Workload Reasonable workload
(if you have good work habits)
No final exam:Only 3mid-terms Every recitation feeds into the
project and lecture Project teams have 2-3 members (exact no. TBD)
Science/Design units: 3 Science, 2 Design Chapter 1 Computer
Abstractions and Technology 7 Homework Assignments and
Project
Assignments consist of two parts Homeworks Individual Effort:
Exercises from the text book Projects Team Effort: Lab assignments
Homework assignments go out on Fridays Assignments due in 10 days
(Mondays) at beginning of lecture Brief (15 minute) quiz on
assignment material in lecture or recitations (several of them)
Must understand assignment to do quiz No late assignments!
Recitations will help solve problems Homeworks will not be graded,
but checked for completeness Solution will be posted on UBlearns
Chapter 1 Computer Abstractions and Technology 8 My Goal Show you
how to understand modern computer architecture in its rapidly
changing form Show you how to design by leading you through the
process on challenging design problems Learn how to test things
Keep interactive So... ask questions come to office hours See the
TA(s) Chapter 1 Computer Abstractions and Technology 9 Project/Lab
Summary Verilog installed on Unix
SPIM available on Unix, Windows Lab assignments 2-3 Projects
Written report Code submission, if necessary Chapter 1 Computer
Abstractions and Technology 10 Grading Grade breakdown No late
homeworks or labs
Three Midterm Exams: 55%(combined) Homeworks:10% Projects:20%
Quizzes:15% No late homeworks or labs Chapter 1 Computer
Abstractions and Technology 11 Morgan Kaufmann Publishers
April 27, 2017 Course Problems Cant make midterm Tell us early and
we will schedule alternate time, if appropriate Forgot to turn in
homework Computer/my cute dog ate whatever No late homeworks or
labs What is cheating? Common examples of cheating: running out of
time on an assignment and take from another and copy, borrow
solution just to take a look, peeking during exam, ... Cheating
will be met with an F for the course Studying together in groups is
not discouraged Work must be your own Better off to skip an
assignment (rather than copying) But it doesnt help on quiz (15% of
grade) anyway Dog: Courtesy.Google images Chapter 1 Computer
Abstractions and Technology 12 Chapter 1 Computer Abstractions and
Technology Project Simulates Industrial Environment
Project teams have 2-3 members in same discussion section Must work
in groups in the real world Communicate with colleagues (team
members) Communication problems are natural What have you done?
What answers you need from others? You must document your work!!!
Everyone must keep an on-line notebook Communicate with supervisor
(TAs) How is the teams plan? Short progress reports are required
What is the teams game plan? What is each members responsibility?
Chapter 1 Computer Abstractions and Technology 13 The Instruction
Set: a Critical Interface
Morgan Kaufmann Publishers April 27, 2017 The Instruction Set: a
Critical Interface software instruction set hardware Computer
organization/computer architecture lays the foundation for the
entire IT industry Patterson The datacenter/cloud is a computer,
your cell phone is a computer, your automobile is a computer Intel
and Microsoft come to your mind intel builds the heart of the
computer, microsoft builds the breath. Why do you want to know
computer architecture? describes the inner workings of the computer
Chapter 1 Computer Abstractions and Technology 14 Chapter 1
Computer Abstractions and Technology How Do the Pieces Fit
Together?
Morgan Kaufmann Publishers April 27, 2017 How Do the Pieces Fit
Together? Application Operating System Compiler Firmware
Instruction Set Architecture Memory system Instr. Set Proc. I/O
system Datapath & Control Digital Design Circuit Design For
class handout Coordination of many levels of abstraction Under a
rapidly changing set of forces Design, measurement, and evaluation
Chapter 1 Computer Abstractions and Technology 15 Chapter 1
Computer Abstractions and Technology How Do the Pieces Fit
Together?
Morgan Kaufmann Publishers April 27, 2017 How Do the Pieces Fit
Together? Application Operating CSE 421 System CSE 443 Compiler
Firmware Instruction Set Architecture Memory system Instr. Set
Proc. I/O system CSE 241 & 341 & 490 Datapath & Control
Digital Design CSE 379 Circuit Design CSE 493 & 452 For lecture
CSE 443 Intro. To language processors Coordination of many levels
of abstraction Under a rapidly changing set of forces Design,
measurement, and evaluation Chapter 1 Computer Abstractions and
Technology 16 Chapter 1 Computer Abstractions and Technology Morgan
Kaufmann Publishers Computer Abstractions and Technology
April 27, 2017 Chapter 1 Computer Abstractions and Technology
Chapter 1 Computer Abstractions and Technology The Computer
Revolution
Morgan Kaufmann Publishers April 27, 2017 The Computer Revolution
1.1 Introduction Progress in computer technology Underpinned by
Moores Law Makes novel applications feasible Computers in
automobiles Cell phones Human genome project World Wide Web Search
Engines Computers are pervasive Chapter 1 Computer Abstractions and
Technology 18 Chapter 1 Computer Abstractions and Technology Morgan
Kaufmann Publishers
April 27, 2017 Classes of Computers Personal computers General
purpose, variety of software Subject to cost/performance tradeoff
Server computers Network based High capacity, performance,
reliability Range from small servers to building sized Chapter 1
Computer Abstractions and Technology 19 Chapter 1 Computer
Abstractions and Technology Classes of Computers Supercomputers
Embedded computers
High-end scientific and engineering calculations Highest capability
but represent a small fraction of the overall computer market
Embedded computers Hidden as components of systems Stringent
power/performance/cost constraints Chapter 1 Computer Abstractions
and Technology 20 Morgan Kaufmann Publishers
April 27, 2017 The PostPC Era Y- Chapter 1 Computer Abstractions
and Technology 21 Chapter 1 Computer Abstractions and Technology
The PostPC Era Personal Mobile Device (PMD) Cloud computing
Battery operated Connects to the Internet Hundreds of dollars Smart
phones, tablets, electronic glasses Cloud computing Warehouse Scale
Computers (WSC) Software as a Service (SaaS) Portion of software
run on a PMD and a portion run in the Cloud Amazon and Google
Chapter 1 Computer Abstractions and Technology 22 Morgan Kaufmann
Publishers
April 27, 2017 What You Will Learn How programs are translated into
the machine language And how the hardware executes them The
hardware/software interface What determines program performance And
how it can be improved How hardware designers improve performance
What is parallel processing Chapter 1 Computer Abstractions and
Technology 23 Chapter 1 Computer Abstractions and Technology
Understanding Performance
Morgan Kaufmann Publishers April 27, 2017 Understanding Performance
Algorithm Determines number of operations executed Programming
language, compiler, architecture Determine number of machine
instructions executed per operation Processor and memory system
Determine how fast instructions are executed I/O system (including
OS) Determines how fast I/O operations are executed Chapter 1
Computer Abstractions and Technology 24 Chapter 1 Computer
Abstractions and Technology Eight Great Ideas Design for Moores
Law
Use abstraction to simplify design Make the common case fast
Performance via parallelism Performance via pipelining Performance
via prediction Hierarchy of memories Dependability via redundancy
1.2 Eight Great Ideas in Computer Architecture Chapter 1 Computer
Abstractions and Technology 25 Morgan Kaufmann Publishers
April 27, 2017 Below Your Program Application software Written in
high-level language System software Compiler: translates HLL code
to machine code Operating System: service code Handling
input/output Managing memory and storage Scheduling tasks &
sharing resources Hardware Processor, memory, I/O controllers 1.3
Below Your Program Chapter 1 Computer Abstractions and Technology
26 Chapter 1 Computer Abstractions and Technology Morgan Kaufmann
Publishers
April 27, 2017 Levels of Program Code High-level language Level of
abstraction closer to problem domain Provides for productivity and
portability Assembly language Textual representation of
instructions Hardware representation Binary digits (bits) Encoded
instructions and data Chapter 1 Computer Abstractions and
Technology 27 Chapter 1 Computer Abstractions and Technology
Components of a Computer
Morgan Kaufmann Publishers April 27, 2017 Components of a Computer
1.4 Under the Covers Same components for all kinds of computer
Desktop, server, embedded Input/output includes User-interface
devices Display, keyboard, mouse Storage devices Hard disk, CD/DVD,
flash Network adapters For communicating with other computers The
BIG Picture Chapter 1 Computer Abstractions and Technology 28
Chapter 1 Computer Abstractions and Technology Morgan Kaufmann
Publishers
April 27, 2017 Touchscreen PostPC device Supersedes keyboard and
mouse Resistive and Capacitive types Most tablets, smart phones use
capacitive Capacitive allows multiple touches simultaneously
Chapter 1 Computer Abstractions and Technology 29 Chapter 1
Computer Abstractions and Technology Through the Looking
Glass
Morgan Kaufmann Publishers April 27, 2017 Through the Looking Glass
LCD screen: picture elements (pixels) Mirrors content of frame
buffer memory Chapter 1 Computer Abstractions and Technology 30
Chapter 1 Computer Abstractions and Technology Morgan Kaufmann
Publishers
April 27, 2017 Opening the Box Capacitive multitouch LCD screen 3.8
V, 25 Watt-hour battery Computer board Chapter 1 Computer
Abstractions and Technology 31 Chapter 1 Computer Abstractions and
Technology Inside the Processor (CPU)
Morgan Kaufmann Publishers April 27, 2017 Inside the Processor
(CPU) Datapath: performs operations on data Control: sequences
datapath, memory, ... Cache memory Small fast SRAM memory for
immediate access to data Chapter 1 Computer Abstractions and
Technology 32 Chapter 1 Computer Abstractions and Technology Morgan
Kaufmann Publishers
April 27, 2017 Inside the Processor Apple A5 Chapter 1 Computer
Abstractions and Technology 33 Chapter 1 Computer Abstractions and
Technology Morgan Kaufmann Publishers
April 27, 2017 Abstractions The BIG Picture Abstraction helps us
deal with complexity Hide lower-level detail Instruction set
architecture (ISA) The hardware/software interface Application
binary interface The ISA plus system software interface
Implementation The details underlying and interface Chapter 1
Computer Abstractions and Technology 34 Chapter 1 Computer
Abstractions and Technology Morgan Kaufmann Publishers
April 27, 2017 A Safe Place for Data Volatile main memory Loses
instructions and data when power off Non-volatile secondary memory
Magnetic disk Flash memory Optical disk (CDROM, DVD) Chapter 1
Computer Abstractions and Technology 35 Chapter 1 Computer
Abstractions and Technology Morgan Kaufmann Publishers
April 27, 2017 Networks Communication, resource sharing, nonlocal
access Local area network (LAN): Ethernet Wide area network (WAN):
the Internet Wireless network: WiFi, Bluetooth Chapter 1 Computer
Abstractions and Technology 36 Chapter 1 Computer Abstractions and
Technology Morgan Kaufmann Publishers
April 27, 2017 Technology Trends Electronics technology continues
to evolve Increased capacity and performance Reduced cost 1.5
Technologies for Building Processors and Memory DRAM capacity Year
Technology Relative performance/cost 1951 Vacuum tube 1 1965
Transistor 35 1975 Integrated circuit (IC) 900 1995 Very large
scale IC (VLSI) 2,400,000 2013 Ultra large scale IC 250,000,000,000
8Gigabit ICs are now available Chapter 1 Computer Abstractions and
Technology 37 Chapter 1 Computer Abstractions and Technology
Semiconductor Technology
Silicon:semiconductor Add materials to transform properties:
Conductors Insulators Switch Chapter 1 Computer Abstractions and
Technology 38 Morgan Kaufmann Publishers
April 27, 2017 Manufacturing ICs Yield: proportion of working dies
per wafer Chapter 1 Computer Abstractions and Technology 39 Chapter
1 Computer Abstractions and Technology Morgan Kaufmann
Publishers
April 27, 2017 Intel Core i7 Wafer 300mm wafer, 280 chips, 32nm
technology Each chip is 20.7 x 10.5 mm Chapter 1 Computer
Abstractions and Technology 40 Chapter 1 Computer Abstractions and
Technology Integrated Circuit Cost
Morgan Kaufmann Publishers April 27, 2017 Integrated Circuit Cost
Nonlinear relation to area and defect rate Wafer cost and area are
fixed Defect rate determined by manufacturing process Die area
determined by architecture and circuit design Chapter 1 Computer
Abstractions and Technology 41 Chapter 1 Computer Abstractions and
Technology Morgan Kaufmann Publishers
April 27, 2017 Defining Performance 1.6 Performance Which airplane
has the best performance? Chapter 1 Computer Abstractions and
Technology 42 Chapter 1 Computer Abstractions and Technology
Response Time and Throughput
Morgan Kaufmann Publishers April 27, 2017 Response Time and
Throughput Response time How long it takes to do a task Throughput
Total work done per unit time e.g., tasks/transactions/ per hour
How are response time and throughput affected by Replacing the
processor with a faster version? Adding more processors? Well focus
on response time for now Chapter 1 Computer Abstractions and
Technology 43 Chapter 1 Computer Abstractions and Technology Morgan
Kaufmann Publishers
April 27, 2017 Relative Performance Define Performance =
1/Execution Time X is n time faster than Y Example: time taken to
run a program 10s on A, 15s on B Execution TimeB / Execution TimeA
= 15s / 10s = 1.5 So A is 1.5 times faster than B Chapter 1
Computer Abstractions and Technology 44 Chapter 1 Computer
Abstractions and Technology Measuring Execution Time
Morgan Kaufmann Publishers April 27, 2017 Measuring Execution Time
Elapsed time Total response time, including all aspects Processing,
I/O, OS overhead, idle time Determines system performance CPU time
Time spent processing a given job Discounts I/O time, other jobs
shares Comprises user CPU time and system CPU time Different
programs are affected differently by CPU and system performance
Chapter 1 Computer Abstractions and Technology 45 Chapter 1
Computer Abstractions and Technology Morgan Kaufmann
Publishers
April 27, 2017 CPU Clocking Operation of digital hardware governed
by a constant-rate clock Clock period Clock (cycles) Data transfer
and computation Update state Clock period: duration of a clock
cycle e.g., 250ps = 0.25ns = 2501012s Clock frequency (rate):
cycles per second e.g., 4.0GHz = 4000MHz = 4.0109Hz Chapter 1
Computer Abstractions and Technology 46 Chapter 1 Computer
Abstractions and Technology Morgan Kaufmann Publishers
April 27, 2017 CPU Time Performance improved by Reducing number of
clock cycles Increasing clock rate Hardware designer must often
trade off clock rate against cycle count Chapter 1 Computer
Abstractions and Technology 47 Chapter 1 Computer Abstractions and
Technology Morgan Kaufmann Publishers
April 27, 2017 CPU Time Example Computer A: 2GHz clock, 10s CPU
time Designing Computer B Aim for 6s CPU time Can do faster clock,
but causes 1.2 clock cycles How fast must Computer B clock be?
Chapter 1 Computer Abstractions and Technology 48 Chapter 1
Computer Abstractions and Technology Instruction Count and
CPI
Morgan Kaufmann Publishers April 27, 2017 Instruction Count and CPI
Instruction Count for a program Determined by program, ISA and
compiler Average cycles per instruction Determined by CPU hardware
If different instructions have different CPI Average CPI affected
by instruction mix Chapter 1 Computer Abstractions and Technology
49 Chapter 1 Computer Abstractions and Technology Morgan Kaufmann
Publishers
April 27, 2017 CPI Example Computer A: Cycle Time = 250ps, CPI =
2.0 Computer B: Cycle Time = 500ps, CPI = 1.2 Same ISA Which is
faster, and by how much? A is faster by this much Chapter 1
Computer Abstractions and Technology 50 Chapter 1 Computer
Abstractions and Technology Morgan Kaufmann Publishers
April 27, 2017 CPI in More Detail If different instruction classes
take different numbers of cycles Weighted average CPI Relative
frequency Chapter 1 Computer Abstractions and Technology 51 Chapter
1 Computer Abstractions and Technology Morgan Kaufmann
Publishers
April 27, 2017 CPI Example Alternative compiled code sequences
using instructions in classes A, B, C Class A B C CPI for class 1 2
3 IC in sequence 1 IC in sequence 2 4 Sequence 1: IC = 5 Clock
Cycles = 21 + 12 + 23 = 10 Avg. CPI = 10/5 = 2.0 Sequence 2: IC = 6
Clock Cycles = 41 + 12 + 13 = 9 Avg. CPI = 9/6 = 1.5 Chapter 1
Computer Abstractions and Technology 52 Chapter 1 Computer
Abstractions and Technology Morgan Kaufmann Publishers
April 27, 2017 Performance Summary The BIG Picture Performance
depends on Algorithm: affects IC, possibly CPI Programming
language: affects IC, CPI Compiler: affects IC, CPI Instruction set
architecture: affects IC, CPI, Tc Chapter 1 Computer Abstractions
and Technology 53 Chapter 1 Computer Abstractions and Technology
Morgan Kaufmann Publishers
April 27, 2017 Power Trends 1.7 The Power Wall In CMOS IC
technology Intel 4004 (108 KHz) in 1971 Intel 8008 (800 KHz) in
1972 Intel 8080 (2M MHz) in 1974 Intel 8086 (5 MHz) in 1978 30 5V
1V 1000 Chapter 1 Computer Abstractions and Technology 54 Chapter 1
Computer Abstractions and Technology Morgan Kaufmann
Publishers
April 27, 2017 Reducing Power Suppose a new CPU has 85% of
capacitive load of old CPU 15% voltage and 15% frequency reduction
The power wall We cant reduce voltage further We cant remove more
heat How else can we improve performance? Chapter 1 Computer
Abstractions and Technology 55 Chapter 1 Computer Abstractions and
Technology Uniprocessor Performance
Morgan Kaufmann Publishers April 27, 2017 Uniprocessor Performance
1.8 The Sea Change: The Switch to Multiprocessors Constrained by
power, instruction-level parallelism, memory latency Chapter 1
Computer Abstractions and Technology 56 Chapter 1 Computer
Abstractions and Technology Morgan Kaufmann Publishers
April 27, 2017 Multiprocessors Multicore microprocessors More than
one processor per chip Requires explicitly parallel programming
Compare with instruction level parallelism Hardware executes
multiple instructions at once Hidden from the programmer Hard to do
Programming for performance Load balancing Optimizing communication
and synchronization Chapter 1 Computer Abstractions and Technology
57 Chapter 1 Computer Abstractions and Technology Morgan Kaufmann
Publishers
April 27, 2017 SPEC CPU Benchmark Programs used to measure
performance Supposedly typical of actual workload Standard
Performance Evaluation Corp (SPEC) Develops benchmarks for CPU,
I/O, Web, SPEC CPU2006 Elapsed time to execute a selection of
programs Negligible I/O, so focuses on CPU performance Normalize
relative to reference machine Summarize as geometric mean of
performance ratios CINT2006 (integer) and CFP2006 (floating-point)
Chapter 1 Computer Abstractions and Technology 58 Chapter 1
Computer Abstractions and Technology Morgan Kaufmann
Publishers
April 27, 2017 CINT2006 for Intel Core i7 920 Chapter 1 Computer
Abstractions and Technology 59 Chapter 1 Computer Abstractions and
Technology Morgan Kaufmann Publishers
April 27, 2017 SPEC Power Benchmark Power consumption of server at
different workload levels Performance: ssj_ops/sec Power: Watts
(Joules/sec) Chapter 1 Computer Abstractions and Technology 60
Chapter 1 Computer Abstractions and Technology SPECpower_ssj2008
for Xeon X5650
Morgan Kaufmann Publishers April 27, 2017 SPECpower_ssj2008 for
Xeon X5650 Chapter 1 Computer Abstractions and Technology 61
Chapter 1 Computer Abstractions and Technology Morgan Kaufmann
Publishers
April 27, 2017 Pitfall: Amdahls Law Improving an aspect of a
computer and expecting a proportional improvement in overall
performance 1.10 Fallacies and Pitfalls Example: multiply accounts
for 80s/100s How much improvement in multiply performance to get 5
overall? Cant be done! Corollary: make the common case fast Chapter
1 Computer Abstractions and Technology 62 Chapter 1 Computer
Abstractions and Technology Fallacy: Low Power at Idle
Morgan Kaufmann Publishers April 27, 2017 Fallacy: Low Power at
Idle Look back at i7 power benchmark At 100% load: 258W At 50%
load: 170W (66%) At 10% load: 121W (47%) Google data center Mostly
operates at 10% 50% load At 100% load less than 1% of the time
Consider designing processors to make power proportional to load
Chapter 1 Computer Abstractions and Technology 63 Chapter 1
Computer Abstractions and Technology Pitfall: MIPS as a Performance
Metric
Morgan Kaufmann Publishers April 27, 2017 Pitfall: MIPS as a
Performance Metric MIPS: Millions of Instructions Per Second Doesnt
account for Differences in ISAs between computers Differences in
complexity between instructions CPI varies between programs on a
given CPU Chapter 1 Computer Abstractions and Technology 64 Chapter
1 Computer Abstractions and Technology Morgan Kaufmann
Publishers
April 27, 2017 Concluding Remarks Cost/performance is improving Due
to underlying technology development Hierarchical layers of
abstraction In both hardware and software Instruction set
architecture The hardware/software interface Execution time: the
best performance measure Power is a limiting factor Use parallelism
to improve performance 1.9 Concluding Remarks Chapter 1 Computer
Abstractions and Technology 65 Chapter 1 Computer Abstractions and
Technology