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Hello,

I'm wondering about the cycle times of the speed-up formula in an unpipelined processor is different to the one in the pipelined version on slide 93 in the script. I would normally assume for such an analysis that these two are the same and can be shortened out.

Thank you
in * TF "Emb. Sys. and Rob." by (150 points)

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I am not sure whether I understand your problem in the right way. The cycle time of a non-pipelined processors is assumed there (naively) as Delta := p * delta where p is the number of pipeline stages and delta is the cycle time of the pipelined processor. Since p is not 1, the two are different, and that is also the case in reality since the pipeline stages are circuits with a much shorter critical path. Hence, the pipelined processor will have a higher clock frequency.

In the second half of slide 93, we assumed Delta := p * delta which allowed us to cancel out delta to estimate the speedup as roughly p. But the following slides shown that this is a too optimistic assumption and that the reality will be less than p.
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