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Computer Architecture

Refers to the attributes of a system that are visible to a programmer.

Instruction Set Architecture (ISA)

Defines instruction formats, opcodes, registers and memory, the effect of executing instructions on registers and memory, and the algorithm for controlling instruction execution.

Architectural Attributes

Examples include the instruction set, the number of bits used to represent various data types, I/O mechanisms, and techniques for addressing memory.

Computer Organization

Refers to operational units and their interconnections that realize the architectural specifications.

Organizational Attributes

Examples include hardware details transparent to the programmer, interfaces between the computer and peripherals, and the memory technology used.

Hierarchical System

Modern computers are arranged in a _____________ that can be explored as interrelated subsystems.

Function

Is the operation of each individual component as part of the structure.

Data Processing

Involves a wide variety of forms and processing requirements

Data Storage

Requires data storage functions for both short-term and long-term data storage.

Data Movement

Involves devices that are either sources or destinations of data requiring some sort of _________________.

Input-Output (I/O)

The process by which data are received from or delivered to a device directly connected to the computer.

Data Communications

The process by which data are moved over longer distances, to or from a remote device.

Control

Manages the computer's resources and directs the performance of the functional parts in response to instructions.

Structure

Is the way in which components are interrelated.

Central Processing Unit (CPU)

Controls the operation of the computer and performs its data processing functions.

Control Unit

Directs the operation of the CPU and, by extension, the computer.

Arithmetic and Logic Unit (ALU)

Performs the computer's data processing functions.

Registers

Provides storage internal to the CPU where the CPU stores input sent to it.

CPU Interconnection

Mechanism that provides for communication among the control unit, ALU, and registers.

Main Memory

Stores short-term data.

System Interconnection

Mechanism that provides for communication among the CPU, main memory, and I/O.

Processor

The computer component that interprets and executes instructions.

Multicore Processor

Refers to a processor containing multiple cores.

Information

Knowledge that reduces uncertainty.

Photonic Computing

Also known as optical computing.

Moore's Law

Observation that the number of transistors in an integrated circuit doubles about every two years.

Hyperthreading

One physical processor can act as two or more logical processors.

Multicore

Refers to processors with multiple cores.

Cache

Memory that stores frequently accessed data for faster access.

Superscalar Execution

is the ability to issue more than one instruction in every processor clock cycle

Branch Prediction

the processor looks ahead in the instruction code fetched from memory and predicts which groups of instructions are likely to be processed next

Pipelining

enables a processor to work simultaneously on multiple instructions by performing a different phase for each instruction at the same time

Data Flow Analysis

the processor checks which instructions are dependent on each other's results or data to create an optimized schedule of instructions

speculatively execute

Using branch prediction and data flow analysis, some processors ____________________ instructions ahead of their actual appearance in the program execution

Cache

is a relatively small, fast memory unit (much faster than main memory) designed to hold recently accessed data, speeding up subsequent access to that data

Fan-In

Increased number of inputs for a single gate means higher RC delay values

Fan-Out

Increased number of connections from an output means higher RC delay values

Contamination Delay

is the lower bound between invalid inputs and invalid outputs, or how long it takes for one invalid signal to mess up the result

Propagation Delay

is the upper bound between new valid inputs and new valid outputs, or how long it takes for the entire system to "settle" after inputs are changed

feature size

the distance between the source and drain on a MOS transistor

Little's Law

theorem used in queueing theory

Clock Speed / Clock Rate

The rate of pulses is known as ________________.

Clock Cycle / Clock Tick

One increment pulse is a ___________.

Clock Period / Cycle Time

The time between pulses is the _______________.

millions of floating-point operations per second (MFLOPS)

Floating-point performance is expressed as _______________________.

Fetch, Decode, Operand fetch, Execute, Store

5 instructions of the instruction cycle.

Registers

are needed to "memorize" an input and "maintain" it as an output

Data processing, Data movement, Data storage, Control

4 Basic Functions that a Computer can Perform

CPU, Main Memory, I/O, System Interconnection

4 Major Structural Components of a Structure

Control Unit, ALU, Registers, CPU Interconnection

4 Major Structural Components of the CPU

Input-Output (I/O)

Moves data between the computer and its external environment

Power, RC Delay, Memory Latency and Throughput

3 Threats to Moore's Law