[計組] 97台大資工

[gsrr (下象棋)]

http://www.lib.ntu.edu.tw/exam/graduate/97/97419.pdf

第二題

(d)Suppose that the application runs for 100 seconds when only one
   processor is used , how many seconds would the application requires
   to run on the 8-processor SMP system?

(e)For the 8-processor run,suppose the disk is transferring data during
   80% of the execution time.What is the minimal execution time even if
   the system has unlimited number of processors?

手上解答為:
(d) 40 seconds
(e) 32 seconds

想請教各位大大:

這兩題題意主要在敘述什麼樣的意思,
(d)及(e)小題又是如何算出?

謝謝!

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推 tureday:(d)的算法是50+50/8＝56.25秒  題目說有50％的時間會造成
→ tureday:Stall，（e）的算法是100*（1-80％）＝20
→ tureday:題目說有80％的執行時間是由八個processor處理如果平行處
推 tureday:理，那80％的時間會被做的很小可以看成0
→ taitin:(e)覺得相反了，因為80%在做disk，只剩20可以加速
推 zeowo:標題錯誤