Chapter 1 (Computer System Overview) Flashcards
Fetches instructions from memory and executes them
CPU
Volatile storage for programs and data
Main memory
Allow data to be moved to and from the computer and I/O devices
I/O modules
The pathway for data and instructions to move between the processor, memory, and I/O modules
System bus
What connects the CPU, I/O Modules, and Main Memory?
System bus
A ____ is a processor contained on a single chip
Microprocessor
How can each core support two logical processors?
Sharing an execution unit
What is a DSP?
Digital Signal Processor
What can a DSP process?
Audio or video streams
A ____ is a set of instructions to be executed in memory
Program
A simplified view of the processor consists of two phases, ____ and ____
Fetch, execute
What does a fetch do?
Retrieves an instruction from memory
What does the execute step do?
Carries out the instruction
An “____” is the processing of a single instruction, involving the fetch cycle and execute cycle
Instruction cycle
What is Processor-memory
Transfer data between processor and memory
What is Processor-I/O
Data transferred to or from a peripheral device
Data processing
Arithmetic or logic operation on data
What is control?
Alter sequence of execution (branch instruction)
Register commonly used for loading and storing values to memory and doing arithmetic
Accumulator register
A mechanism for interrupting the processor’s execution in order to do something else
Interrupt
What are some common types of interrupts?
Program
Timer
I/O
Hardware failure
____ improve processor utilization by notifying the processor of an event versus making the processor wait
Interrupts
What if we didn’t have interrupts?
The processor would have to keep checking to see if an event has occurred
What must the processor do before executing the interrupt handler?
Save the system state (the registers) on the stack
T/F It is possible for an interrupt to occur while another interrupt is being processed
T
Memory on a computer system is composed of a ____
Hierarchy
T/F Program execution of instructions and data occurs in clusters
T
The ____ is the fraction of memory accesses that are found in the cache
Hit ratio
What are some considerations in cache design?
Cache size Block size Mapping function Replacement algorithm Write policy
What does the mapping function do?
Determines where to put a new block
What does the replacement algorithm do?
Determines how to replace a block
What is the write policy?
When to write a block back to main memory
Processor moves data between I/O module and memory
Programmed I/O
Processor issues I/O command and then goes on to other processing
Interrupt-driven I/O
Processor delegates the I/O transfer to the DMA module
DMA (Direct Memory Access)
What are some SMP advantages?
Performance
Availability
Incremental growth
Scaling
What does SMP stand for?
Symmetric Multiprocessors
One reason for multicores is the…
Limitations of continuing to improve a single processor
