Computer Architecture - C952 Practice Questions 2024

SIMD-same instruction many data streams -aanswers The same instruction is applied to many data streams, as in a vector processor. MIMD-many instructions many data streams -aanswers A multiprocessor SPMD-Single program many data streams -aanswers The conventional MIMD programming model, where a single program runs across all processors. SISD-single instruction single data stream -aanswers A uniprocessor DRAM-dynamic random access -aanswers 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. SRAM-static random access memory -aanswers Also memory built as an integrated circuit, but faster and less dense than DRAM Spatial locality -aanswers The locality principle stating that if a data location is referenced, data locations with nearby addresses will tend to be referenced soon. Temporal locality -aanswers The principle stating that if a data location is referenced then it will tend to be referenced again soon. Superscalar -aanswers An advanced pipelining technique that enables the processor to execute more than one instruction per clock cycle by selecting them during execution. Amdahl's Law -aanswers A rule stating that the performance enhancement possible with a given improvement is limited by the amount that the improved feature is used. It is a quantitative version of the law of diminishing returns. Weak Scaling -aanswers Speed-up achieved on a multiprocessor while increasing the size of the problem proportionally to the increase in the number of processors. Strong Scaling -aanswers Speed-up achieved on a multiprocessor without increasing the size of the problem. Translation-Lookaside Buffer (TLB) -aanswers A cache that keeps track of recently used address mappings to try to avoid an access to the page table. Parallelization -aanswers Pipelining -aanswers An implementation technique in which multiple instructions are overlapped in execution, much like an assembly line. Memory -aanswers The storage area in which programs are kept when they are running and that contains the data needed by the running programs. Control -aanswers The component of the processor that commands the datapath, memory, and I/O devices according to the instructions of the program. GPU-(graphics processing unit) -aanswers The Graphics processing unit. Cloud computing -aanswers the practice of using a network of remote servers hosted on the Internet to store, manage, and process data, rather than a local server or a personal computer. ALU -aanswers Hardware that performs addition, subtraction, and usually logical operations such as AND and OR RAID 0-no redundancy, striping -aanswers data is written across multiple disks. There is no redundancy. Performance is improved. RAID 1-mirroring, redundancy -aanswers Mirrors the data on 2 drives. RAID 2-error detecting and correcting code, not used -aanswers RAID 3-bit interleaved parity -aanswers RAID 4- block interleaved parity -aanswers RAID 5- distributed block-interleaved parity -aanswers RAID 6- P&Q redundancy -aanswers Program counter -aanswers The register containing the address of the instruction in the program currently being executed. Cache memory -aanswers A small, fast memory that acts as a buffer for a slower, larger memory. Machine language -aanswers A binary representation of machine instructions. Assembly language -aanswers A symbolic representation of machine instructions. Operating system -aanswers Supervising program that manages the resources of a computer for the benefit of the programs that run on the computer Systems software -aanswers Software that provides services that are commonly useful, including operating systems, compilers, loaders, and assemblers. Transistor -aanswers An on/off switch controlled by an electric signal. Integrated circuit -aanswers Also called a chip. A device combining dozens to millions of transistors. Volatile memory -aanswers Storage, such as DRAM, that retains data only if it is receiving power. Nonvolatile memory -aanswers Storage that retains data even when powered down (such as flash memory, hard disk, or DVD storage). Flash memory -aanswers 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.