推 ccpz: 第一題你的想法應該沒錯，只有那個不會改變系統狀態 02/02 08:56
這兩題出自中興103年資管所計概考題，不知道是自己基本功差還是題目含糊
總有些不確定...
a privileged instruction may be executed only while the hardware is
in kernel mode. Which of the following statments is LEAST likely to
be a privileged instruction?
(A) An instruction that sends output to a printer
(B) An instruction that modifies a memory management register
(C) An instruction that halts the CPU
(D) An instruction that resets the computer's time-of-day clock
(E) An instruction that reads the computer's time-of-day clock
據我所知privileged instruction是指那些容易造成系統危險的指令，
因此要在kernel mode執行，通常對硬體進行操作的指令都是特權指令
這題我是猜E，不知道判斷有無錯誤
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which of the following statements is not the method to remove a deadlock:
(A) Resource-allocation graph algorithm can be used to detect the deadlock
(B) Require each process to requect all its resoureces at one time.
(C) Convert nonsharable resources into sharable resources.
(D) Terminate all processes involved in the deadlock.
(E) Terminate processes one by one until the deadlock is broken.
這題D、E是移除死結的方法，而B、C則是預防的方法，A為避免死結的方法之一
某補教名師在鼎茂賣的解答寫(B)，說明是寫"允許每一行程申請其所有需要資源，
則可能發生deadlock"，據我所知(B)不會發生死結，只有可能發生starvation
如果要我選的話，可能會選(A)，這演算法好像只用於single instance的情況
不知道有無錯誤，煩請各位指點
謝謝
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※ 編輯: Nexus5566 (39.8.4.123), 02/01/2016 14:25:01