Category: ACA

CISC [Complex instruction set Computing]

It is very large instruction sets ,more than 300 separate instructions. Performance was improved by allowing the simplification of program compilers. The range of more advanced instructions available. Expensive to produce. More specialized addressing modes and registers also being implemented, with variable length instruction codes. Instruction pipelining cannot be implemented easily. Many complex instructions can […]

RISC [Reduced instruction set Computing]

It is small set of instructions. It contains at most 100 instructions set. Because of simple instructions, RISC chips require fewer transistors to produce processors. Also the reduced instruction set means that the processor can execute the instructions morequickly, potentially allowing for greater speeds. Allowing simple instructions causes a heavy load on the software’s. Greater […]

Data and Resource dependencies:

Data Dependences: Instruction i produces a result that may be used by instruction j, or Instruction j is data dependent on instruction k, and instruction k is data dependent on instruction i. The second condition simply states that one instruction is dependent on another if there exists a chain of dependences of the first type […]

Multivector and SIMD computers

Vector Computer: In a vector computer, a vector processor is attached to the scalar processor as an optional feature. The host computer first loads program and data to the main memory. Then the scalar control unit decodes all the instructions. If the decoded instructions are scalar operations or program operations, the scalar processor executes those […]

Parallel computer models – Multiprocessors and Multicomputers

Multiprocessor and multicomputer are distinguished by a shared common memory and unshared distributed memories. Shared Memory multiprocessor- Three most common shared memory multiprocessors models are – Uniform Memory Access (UMA) Non-uniform Memory Access (NUMA) Cache Only Memory Architecture (COMA) 1. Uniform Memory Access (UMA) In this model, all the processors share the physical memory uniformly.All […]

Flynn’s Classification

Flyns classification depends on Data stream and Instruction stream. Data stream- A data stream is the operations performed by the processor on data. A data stream is sequence of data having input, partial or temporary result. Instruction stream- A instruction stream is the fetch and execution of data stream by the machine. Based on the multiple data […]