1. Concept
The operating cycle of the instruction pipeline is greater than or equal to the operating time of the instruction with the longest execution time among the instructions.
Although it can be executed in parallel, the completion time is at least the operating time of the longest instruction.
2. Rewriting questions
topic:
A four-level instruction pipeline completes the four operations of fetching, fetching, calculating, and saving the results respectively, and the completion time is 8ns, 9ns, 4ns, and 8ns, then the pipeline operation cycle is at least ____ ns.
A 4
B 8
C 9
D 33
Analysis:
Even if you don’t understand the concept, at least you can guess that it is either the longest time 9 or the cumulative time 29. If there is no 29, you can only choose 9 and send a sub-question.