Question type III ： Mixed index

Number of blocks that can be indicated per block = Disk block size / Block number size

Number of indirect index blocks = Number of blocks that can be indicated per block ^n Order power

Maximum total file blocks = Number of direct indexes + Number of L1 indirect index blocks + Number of secondary indirect index blocks +……

Maximum file bytes = Maximum total file blocks * Disk block size

Direct example ：

*
The file directory entry of a file system contains 6 An array of tables is used to describe the physical structure of the file , Before the array 4 Entries used as direct indexes , Section 5 Entries are first level indirect indexes , The last entry is used as a secondary indirect index , The size of the disk block is 512 byte , Block number 2 byte . Please answer the following questions ：
(1) How many bytes can the file system construct ?

(2) A file file have 268KB, Please draw the index structure of the file data block .

(1) Each piece 512 byte , Block number 2 byte , Then each data block can indicate 256 block ,

Then the total number of blocks of the maximum file ：4+256^1+256^2=65796,

(4 Before representation 4 Entries used as direct indexes , Except direct index , Number of indirect index blocks = Number of blocks that can be indicated per block ^n Order power )

Number of bytes is ：65796*512.

(2) 268K Required occupation 268K/512=523 block ,（512 Is the disk block size ）

523=4+256^1+263,523 stay 4+256^1 and 4+256^1+256^2 between , So the secondary index is used .

Index structure diagram ： Box is the logical block number of the file , from 0 Start number

thank you “ Green peach and dew ”5 month 22 You gave it to me 8 Gross money

thank you “qq_52937762”5 month 23 You gave it to me 1.6 element

Technology