Q 32,paper 2,june 12.Cached and interleaved memories are ways of speeding up memory access between CPU’s and slower RAM. Which memory models are best suited (i.e. improves the performance most) for which programs ?

Options (i) Cached memory is best suited for small loops.
(ii) Interleaved memory is best suited for small loops
(iii) Interleaved memory is best suited for large sequential code.
(iv) Cached memory is best suited for large sequential code.
(A) (i) and (ii) are true.
(B) (i) and (iii) are true.
(C) (iv) and (ii) are true.
(D) (iv) and (iii) are true.
Answer (B)
interleaved memory is a design made to compensate for the relatively slow speed of dynamic random-access memory (DRAM) or core memory, by spreading memory addresses evenly across memory banks. That way, contiguous memory reads and writes are using each memory bank in turn, resulting in higher memory throughputs due to reduced waiting for memory banks to become ready for desired operations. Cache is effective in loops because same variables are used in a loop repeatedly hence improves the speed if variables are kept in cache.