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kayvonf

Question: Can you draw correspondences between concepts in the laundry example, the highway example, and the instruction pipeline example? What corresponds to what?

pdp

In the highway example,

  1. if there is only one lane and only one car can go through that lane, its equivalent to having a single washing machine with a single round of all three operations to be performed together one after another before the next round as well as having a single pipeline of fetch, decode, execute and write for one instruction to be processed fully before the next.

  2. If there is only one lane but multiple cars can go through it, then its equivalent to having one washing machine, which can wash clothes and then send it to its dryer and pick up next set of clothes and its dryer finishing one set of drying and sending it for folding and so on. It is also equivalent to having one fetch unit which fetches an instruction and sends it to the decoder and fetches the next instruction, the decoder decodes one instruction and sends it to execute and decodes the next and so on.

  3. If there are multiple lanes of cars and multiple cars on each lane, then its equivalent to having multiple washing machines and multiple fetch decode execute units with functionalities of point 2.