作者ping990579 (小山青)
看板Grad-ProbAsk
標題[理工] 103交大資聯計系i-node
時間Mon Oct 31 22:46:07 2022
Consider a file system that uses i node-like structure (combined scheme with
multilevel indices) to represent files. Disk blocks are 8-KB in size and a
pointer to a disk block requires 4 bytes. To record a file, this file system
has 12 pointers in the primary index block, composed of 9 direct block pointers, and a single, a double, and a triple indirect
block pointers. the space of other indirect index blocks is fully used to
store pointers. If we want to access the first to the 5120 logical disk
blocks of a file, how many physical disk blocks must be read from the disk?
(Hint: please take into account the primary and other index blocks)
(A) 5120
(B)5121
(C) 5123
(d) 5125
(E) None of the above number is correct
https://imgur.com/a/Q5fgqFy
請問是哪裡有算錯嗎
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※ 編輯: ping990579 (123.241.202.132 臺灣), 10/31/2022 22:49:14
1F：→ me356500: 少一個access primary吧 11/01 14:28
2F：推 bettyteng21: 5124加上最一開始的，就是5125 11/28 18:15
有點聽不太懂，我後來爬到有人也問一樣的問題，我一開始是這樣算的，總共循序5120
個，這5120個會在兩層的第二塊裡面，所以我原本是5120+一次(存取single)+一次(存取
double)+一次(double的第一塊)+一次(double的第二塊)=5124，但好像還要再額外一次
存取double，所以總共5125，這樣不知道對不對
※ 編輯: ping990579 (116.241.187.215 臺灣), 12/15/2022 20:52:03