申論題

20. (5 points) Assume that we have an interconnection network topology on the clock cycles per instruction (CPI) of programs running on a distributed-memory mutiprocessor. The processor clock rate is 6.3 GHz and the base CPI of an application with all references hitting in the cache is 0.75. Assume that 0.2% of the instructions involve a remote communication reference. The cost of a remote communication reference is (100 + 10h) ns, where h is the number of communication network hops that a remote reference has to make to the remote processor memory and back.Assume that all communication links are bidirectional.Please answer which of the following statements is/are correct.

(c) When the system is a 32-node ring, the average CPI of the application is larger than 1.1.