作者a613204 (胖胖)
看板Grad-ProbAsk
標題[理工] [計組] load use data hazard
時間Sat Sep 24 16:41:00 2011
Consider a MIPS machine with a 5-stage pipeline with a cycle time of 10ns.
Assume that you are executing a program where a fraction,f,of all instructions
immediately follow a load upon which they are dependent.
With forwarding enabled what is the total execution time for N instructions,
in terms of f?
這裡給的答案是[(5-1)+N+N*f]
覺得有點怪
不是兩個指令之間必須要暫停一個cycle嗎??
為什麼是N*f?? 不是N*f/2
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◆ From: 123.0.42.10
推 wheels:因為有forwording所以load use data hazard只需停一次 09/24 22:39
→ wheels:又總共有N*f個load use data hazard，所以多停N*f次 09/24 22:40
→ wheels:說說你N*f/2的想法看看?? 09/24 22:41
推 feabries:原PO會不會是誤會題目意思 以為f是指load+後面的inst. 全 09/25 00:32
→ feabries:部的比例? 09/25 00:32
→ feabries:原來已經有回文@@ 09/25 00:33