[問題] 計組-管線計算

[bernachom (Terry)]

  請教一題計算

  Suppose that 20% of the instruction are loads, and half of the time

  the instruction following a load insruction depends on the result of

  the lod. If this hazard creates a single-cycle delay, how much faster

  is an idea pipelined machine (with CPI of 2) that does not delay the

  pipeline, compard to this realistic pipeline that may create a single-

  cycle load stall delay?(Ignore any stalls other than load stalls)

  書上寫:

  cpi=2+ 20% *50% *1 =2.1

  perfect pipeline machine 快了 2.1/2=1.05


  請教一下，cpi第一個式子，那個*1 是在乘什麼呢? 謝謝

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→ bernachom:是因為題目沒說明，所以預設為1嗎?
→ uminchu185:題目有說,英文第三行,if this hazard...
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