1.1.2 Flashcards
CISC
Complex Instruction Set Computer
used mainly in computers
aims to complete the task in as few lines of assembly as possible – this means the processor hardware and circuitry has to be more complicated so it can understand and execute a series of operations
CISC pros
The compiler has to do very little work to translate the high-level language statement into assembly
more efficient use of RAM
CISC cons
might take more than one machine/clock cycle to execute each instruction
expensive
no pipelining
more complex hardware
RISC
Reduced Instruction Set Computer
aim to use simple instructions that will be executed within a single machine/clock cycle
RISC cons
The compiler has to do more conversion work
More RAM is needed to store the assembly instructions
The process seems less efficient
GPU
graphics processing unit - a specialised electronic circuit - very efficient at manipulating computer graphics and image processing - has 1000s of small efficient cores for parallel processing - can also perform complex numerical calculations on matrices/vectors/multiple data at the same time
multicore systems
Single chip containing multiple independent processing units but have: On-chip shared cache and Inter-core communication
2 cores = dual-core processor
4 cores = quad-core processor
2 cores != 2x faster because some programs can not use all cores at once
CMP
CMP containing multiple CPU cores
used in multicore systems
parallel processing
VERY SIMILAR TO PIPELINING
The processing of program instructions by dividing them between multiple processors or processor cores
e.g. one core always Fetching, one always Decoding, one always Executing
RISC pros
require fewer transistors and less complex hardware, leaving more room for general-purpose registers and cache
As all instructions are uniform in execution time, pipelining is possible
Lower energy requirements
