申論題

8.w ral a may DiEen a heftoueat There are two DRAM channels.

Each channel has two ranks of DRAM chips.

Each memory channel is controlled by a separate memory controller.

Each rank of DRAM contains eight banks.

Each bank contains 32K rows.

Each row in one bank is 8KB.
Assume the minimum retention time among all DRAM rows in the system is 64 ms. In order to ensure
that no data is lost, every DRAM row is refreshed once per 64 ms. Every DRAM row refresh is
initiated by a command from memory controller which occupies the command bus on the associated
memory channel. Consider a 1.024 second span of time.Define the utilization (of a resource such as a bus or a memory bank) as the fraction of total time for which a resource is occupied by a refresh command. For each calculation in this question, you may leave your answer in simplified form in terms of powers of 2 and powers of 10.