推 lightergogo:(2)read:20(讀到第20個data) write:2(改變2次指標) 03/02 20:47
→ bigrat2:在請問一下 連續的（3)為什麼是38不是40呢？ 03/02 22:46
推 lightergogo:從第22個block開始 往前搬一格 每次都要read&write 03/02 23:02
→ lightergogo:搬了(40-22+1)=19 次 所以19*2=38 03/02 23:03
※ 引述《b76516 (阿聰)》之銘言：
: 剛好先前有鄉民問到同一題引用一下
我想請問 linked 的(2)(3)(4)
為什麼是22.22.40 呢？
謝謝大家的指教
: 4. Consider a file consisting of 40 blocks. Assume that the file control block
: (and the index block, in case of indexed allocation) is already in memory.
: Calculate how many disk I/O operations are required for contiguous, linked,
: and indexed(single-level) allocation strategies, if, for one block, the
: following conditions hold. In the contiguous allocation case, assume that
: there is no room to grow in the beginning, but there is room to grow in the
: end. Assume that the block information to be added is stored in memory.
: (1)The block is added at the beginning.
: (2)The block is added in the middle.
: (3)The block is removed from the middle.
: (4)The block is removed from the end.
: 答案寫說
: contiguous linked indexed
: (1) 81 1 1
: (2) 41 22 1
: (3) 38 22 0
: (4) 0 40 0
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