Consider a memory system with addresses spaced at a distance m, bank cycle time T and n banks. The average data access time per word in synchronous organization is

1. At = m·T/n for m << n; T for m >> n
2. Bt = T/n for m << n; T for m >> n
3. Ct = m·T for m << n; T for m >> n
4. Dt = m·T for m << n; m/T for m >> n

Pick an option to check yourself, or open the answer below.

Show answer & explanation

Correct answer: A. t = m·T/n for m << n; T for m >> n

Explanation

With stride m, successive accesses fall in banks m apart, so only about n/m banks work in parallel: t ≈ m·T/n when m is much smaller than n. When m ≥ n, every access hits the same bank and must wait a full cycle T.