作者gn00618777 (123)
看板Grad-ProbAsk
标题[理工] [计组]-效能
时间Fri Sep 18 22:22:01 2009
A certain machine with a 10ns(10*10^9s) clock period can
perform jump(1 cycle),branches(3 cycles),arithmetic intruction(2 cycles)
multiply intructions(5 cycles),and memory intruction(4 cycles).
A certain program has 10% jumps, 10% branches,50% arithmetic,10%
multiply. and 20% memory intructions.
What is the CPI of this program on this machine?
解答是说 clock=10ns
不是求CPI吗?
题木我只看的懂说指令 jump CPI=1
branches CPI=3
arithmetic CPI=2
multiply CPI=5
memory CPI=4 (其实也不知道我这样对不对)..
至於10ns是啥我不了捏
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1F:→ gn00618777:10ns是clock cycle time吗?一个周期的时间长度? 09/18 22:30
2F:推 ianwuzack:对阿 是clock cycle time没错 09/18 22:39
3F:→ gn00618777:那clock = 10ns又是怎回事 不是求cpi吗? 09/18 22:40
4F:推 ianwuzack:这题我有看过 这只是其中一个问题而已 09/18 22:42
5F:→ ianwuzack:下面会接着求Eexcution time 09/18 22:43
6F:→ gn00618777:阿 我懂了..没事了呵呵.. 09/18 22:44
7F:→ gn00618777:对阿 这是呆大电机考题 09/18 22:53
8F:→ gn00618777:计组没补习 超难看的懂= =" 09/18 22:53