WGU C952 questions with complete solutions
Register File
A state element that consists of a set of registers that can be read and written by
supplying a register number to be accessed.
provides 1024 scalar 32-bit registers for up to 64 threads.
machine language
The language made up of binary-coded instructions that is used directly by the
computer
system software
The set of programs that enables a computer's hardware devices and application
software to work together; it includes the operating system and utility programs.
operating system
(computer science) software that controls the execution of computer programs and may
provide various services
Assembly Language
Programming language that has the same structure and set of commands as machine
languages but allows programmers to use symbolic representations of numeric machine
code.
IBM 360/91
Introduced many new concepts, including dynamic detection of memory hazards,
generalized forwarding, and reservation stations. Tomasulo's algorithm
The internal organization of the 360/91 shares many features with the Pentium III and
Pentium 4, as well as with several other microprocessors. One major difference was
that there was no branch prediction in the 360/91 and hence no speculation. Another
major difference was that there was no commit unit, so once the instructions finished
execution, they updated the registers.
Dynamic Random Access Memory (DRAM)
Memory built as an integrated circuit; it provides random access to any location. Access
times are 50 nanoseconds and cost per gigabyte in 2012 was $5 to $10.
Multiple DRAMs are used together to contain the instructions and data of a program. In
contrast to sequential access memories, such as magnetic tapes, the RAM portion of
the term DRAM means that memory accesses take basically the same amount of time
no matter what portion of the memory is read.
Modern DRAMS consist of rows in each bank
frame buffering
A portion of RAM containing a bitmap that drives a video display. It is a memory buffer
containing a complete frame of data.
The image to be represented onscreen is stored in the frame buffer, and the bit pattern
per pixel is read out to the graphics display at the refresh rate. The animation below
shows a frame buffer with a simplified design of just 4 bits per pixel.
,Datapath
The component of the processor that performs arithmetic operations
Control
The component of the processor that commands the datapath, memory, and I/O
devices according to the instructions of the program.
Integrated circuit
Also called a chip. A device combining dozens to millions of transistors.
Central processor unit (CPU)
Also called processor. The active part of the computer, which contains the datapath and
control and which adds numbers, tests numbers, signals I/O devices to activate, and so
on.
Static random access memory (SRAM)
Also memory built as an integrated circuit, but faster and less dense than DRAM.
Instruction set architecture
Also called architecture. An abstract interface between the hardware and the lowest-
level software that encompasses all the information necessary to write a machine
language program that will run correctly, including instructions, registers, memory
access, I/O, and so on.
Application binary interface (ABI)
The user portion of the instruction set plus the operating system interfaces used by
application programmers. It defines a standard for binary portability across computers.
Volatile memory
Storage, such as DRAM, that retains data only if it is receiving power.
Nonvolatile Memory
A form of memory that retains data even in the absence of a power source and that is
used to store programs between runs. A DVD disk is nonvolatile.
Magnetic disk
Also called hard disk. A form of nonvolatile secondary memory composed of rotating
platters coated with a magnetic recording material. Because they are rotating
mechanical devices, access times are about 5 to 20 milliseconds and cost per gigabyte
in 2012 was $0.05 to $0.10
Main memory
Also called primary memory. Memory used to hold programs while they are running;
typically consists of DRAM in today's computers.
Secondary memory
Nonvolatile memory used to store programs and data between runs; typically consists of
flash memory in PMDs and magnetic disks in servers.
Flash memory
A nonvolatile semiconductor memory. It is cheaper and slower than DRAM but more
expensive per bit and faster than magnetic disks. Access times are about 5 to 50
microseconds and cost per gigabyte in 2012 was $0.75 to $1.00.
Single Instruction Single Data (SISD)
A uniprocessor
Multiple Instruction Multiple Data (MIMD)
A multiprocessor.
Single Program, Multiple Data Streams (SPMD)
, The conventional MIMD programming model, where a single program runs across all
processors.
Single Instruction Stream, Multiple Data Streams (SIMD)
The same instruction is applied to many data streams, as in a vector processor.
Data-level parallelism
Parallelism achieved by performing the same operation on independent data
vector-based code
conventional code
LEGv8
assembly instructions
multimedia extensions (MMX)
An expanded set of instructions supported by a processor that provides multimedia-
specific functions.
data hazard (pipeline data hazard)
When a planned instruction cannot execute in the proper clock cycle because data that
is needed to execute the instruction are not yet available.
forwarding (bypassing)
A method of resolving a data hazard by retrieving the missing data element from
internal buffers rather than waiting for it to arrive from programmer-visible registers or
memory
Structural hazard
When a planned instruction cannot execute in the proper clock cycle because the
hardware does not support the combination of instructions that are set to execute.
Pipelining
Technique that allows the CPU to work on more than one instruction at a time
Formula
total process time = [longest task * (total load -1)] + total load time
R-format ALU operations
Requires register file and the ALU.
Program Counter (PC)
The register that contains the address of the next instruction to be executed
output
The results of the operation of any system.
temporal locality
The principle stating that if a data location is referenced then it will tend to be referenced
again soon.
spatial locality
The principle stating that if a data location is referenced, data locations with nearby
addresses will tend to be referenced soon.
Memory hierarchy
A structure that uses multiple levels of memories; as the distance from the processor
increases, the size of the memories and the access time both increase.
Block (or line)
The minimum unit of information that can be either present or not present in a cache.
Hit rate
Register File
A state element that consists of a set of registers that can be read and written by
supplying a register number to be accessed.
provides 1024 scalar 32-bit registers for up to 64 threads.
machine language
The language made up of binary-coded instructions that is used directly by the
computer
system software
The set of programs that enables a computer's hardware devices and application
software to work together; it includes the operating system and utility programs.
operating system
(computer science) software that controls the execution of computer programs and may
provide various services
Assembly Language
Programming language that has the same structure and set of commands as machine
languages but allows programmers to use symbolic representations of numeric machine
code.
IBM 360/91
Introduced many new concepts, including dynamic detection of memory hazards,
generalized forwarding, and reservation stations. Tomasulo's algorithm
The internal organization of the 360/91 shares many features with the Pentium III and
Pentium 4, as well as with several other microprocessors. One major difference was
that there was no branch prediction in the 360/91 and hence no speculation. Another
major difference was that there was no commit unit, so once the instructions finished
execution, they updated the registers.
Dynamic Random Access Memory (DRAM)
Memory built as an integrated circuit; it provides random access to any location. Access
times are 50 nanoseconds and cost per gigabyte in 2012 was $5 to $10.
Multiple DRAMs are used together to contain the instructions and data of a program. In
contrast to sequential access memories, such as magnetic tapes, the RAM portion of
the term DRAM means that memory accesses take basically the same amount of time
no matter what portion of the memory is read.
Modern DRAMS consist of rows in each bank
frame buffering
A portion of RAM containing a bitmap that drives a video display. It is a memory buffer
containing a complete frame of data.
The image to be represented onscreen is stored in the frame buffer, and the bit pattern
per pixel is read out to the graphics display at the refresh rate. The animation below
shows a frame buffer with a simplified design of just 4 bits per pixel.
,Datapath
The component of the processor that performs arithmetic operations
Control
The component of the processor that commands the datapath, memory, and I/O
devices according to the instructions of the program.
Integrated circuit
Also called a chip. A device combining dozens to millions of transistors.
Central processor unit (CPU)
Also called processor. The active part of the computer, which contains the datapath and
control and which adds numbers, tests numbers, signals I/O devices to activate, and so
on.
Static random access memory (SRAM)
Also memory built as an integrated circuit, but faster and less dense than DRAM.
Instruction set architecture
Also called architecture. An abstract interface between the hardware and the lowest-
level software that encompasses all the information necessary to write a machine
language program that will run correctly, including instructions, registers, memory
access, I/O, and so on.
Application binary interface (ABI)
The user portion of the instruction set plus the operating system interfaces used by
application programmers. It defines a standard for binary portability across computers.
Volatile memory
Storage, such as DRAM, that retains data only if it is receiving power.
Nonvolatile Memory
A form of memory that retains data even in the absence of a power source and that is
used to store programs between runs. A DVD disk is nonvolatile.
Magnetic disk
Also called hard disk. A form of nonvolatile secondary memory composed of rotating
platters coated with a magnetic recording material. Because they are rotating
mechanical devices, access times are about 5 to 20 milliseconds and cost per gigabyte
in 2012 was $0.05 to $0.10
Main memory
Also called primary memory. Memory used to hold programs while they are running;
typically consists of DRAM in today's computers.
Secondary memory
Nonvolatile memory used to store programs and data between runs; typically consists of
flash memory in PMDs and magnetic disks in servers.
Flash memory
A nonvolatile semiconductor memory. It is cheaper and slower than DRAM but more
expensive per bit and faster than magnetic disks. Access times are about 5 to 50
microseconds and cost per gigabyte in 2012 was $0.75 to $1.00.
Single Instruction Single Data (SISD)
A uniprocessor
Multiple Instruction Multiple Data (MIMD)
A multiprocessor.
Single Program, Multiple Data Streams (SPMD)
, The conventional MIMD programming model, where a single program runs across all
processors.
Single Instruction Stream, Multiple Data Streams (SIMD)
The same instruction is applied to many data streams, as in a vector processor.
Data-level parallelism
Parallelism achieved by performing the same operation on independent data
vector-based code
conventional code
LEGv8
assembly instructions
multimedia extensions (MMX)
An expanded set of instructions supported by a processor that provides multimedia-
specific functions.
data hazard (pipeline data hazard)
When a planned instruction cannot execute in the proper clock cycle because data that
is needed to execute the instruction are not yet available.
forwarding (bypassing)
A method of resolving a data hazard by retrieving the missing data element from
internal buffers rather than waiting for it to arrive from programmer-visible registers or
memory
Structural hazard
When a planned instruction cannot execute in the proper clock cycle because the
hardware does not support the combination of instructions that are set to execute.
Pipelining
Technique that allows the CPU to work on more than one instruction at a time
Formula
total process time = [longest task * (total load -1)] + total load time
R-format ALU operations
Requires register file and the ALU.
Program Counter (PC)
The register that contains the address of the next instruction to be executed
output
The results of the operation of any system.
temporal locality
The principle stating that if a data location is referenced then it will tend to be referenced
again soon.
spatial locality
The principle stating that if a data location is referenced, data locations with nearby
addresses will tend to be referenced soon.
Memory hierarchy
A structure that uses multiple levels of memories; as the distance from the processor
increases, the size of the memories and the access time both increase.
Block (or line)
The minimum unit of information that can be either present or not present in a cache.
Hit rate
