(1)Suppose a non-preemptive scheduler uses variable priorities
and time quanta as the following table,where the highest priority is 5
Priority Time quantum New priority after New priority after
time quantum is expired returning from I/O
5 40 4 5
4 60 3 5
3 100 2 4
2 200 1 4
1 320 1 3
Which of the following statements is "incorrect"?
(A)Response time of interactive threads will increase.
(B)Priorities of CPU-intensive threads will be lowered.
(C)Time-quanta of I/O-bound threads will decrease.
(D)None of the above.
我的想法是Response time是第一次回應時間 所以RR的Quantum就是Response time
但優先權2和1的Process變為同樣優先權所以A是錯的
B的話CPU就是和I/O的優先權值相反 這樣對嗎?
C的話我就不知道要看哪一個了
(2)另外我想知道有沒有開放式課程是講同步問題的MAILBOX
有點不是很清楚Blocking receive , Non-Blocking receive之類system call的用法
還有分類題庫有看到的serializable transaction問題洪逸好像也沒教過
不知道有沒有網頁講的比較清楚的呢
謝謝各位撥空看我的問題
希望可以獲得解答^^
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