Q 48,paper 2,June12. Pipelining strategy is called implement

Options (A) instruction execution (B) instruction prefetch (C) instruction decoding (D) instruction manipulation
Answer(B) Instruction prefetch. In computer architecture, instruction prefetch is a technique used in microprocessors to speed up the execution of a program by reducing wait states. Modern microprocessors are much faster than the memory , meaning that the program's instructions cannot be read fast enough to keep the microprocessor busy. Adding a cache can provide faster access to needed instructions. Prefetching occurs when a processor requests an instruction from main memory before it is actually needed. Once the instruction comes back from memory, it is placed in a cache. When an instruction is actually needed, the instruction can be accessed much more quickly from the cache than if it had to make a request from memory. Since programs are generally executed sequentially, performance is likely to be best when instructions are prefetched in program order. Alternatively, the prefetch may be part of a complex branch prediction algorithm, where the processor tries to anticipate the result of a calculation and fetch the right instructions in advance