面试笔记2

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                                        文件和大目录

1： 如何查找大文件？

文件，比如文件大小超过100M或1G（阀值视具体情况而定）。那么如何把这些大文件搜索出来呢？搜索当前目录下，超过800M大小的文件

[root@getlnx01 u03] 
/u03
[root@getlnx01 u03]
./flash_recovery_area/backup/backupsets/ora_df873519197_s46815_s1
./flash_recovery_area/backup/backupsets/ora_df873523646_s46822_s1
./flash_recovery_area/backup/backupsets/ora_df873521714_s46818_s1
./flash_recovery_area/backup/backupsets/ora_df873522876_s46820_s1
./flash_recovery_area/backup/backupsets/ora_df873517396_s46813_s1
./flash_recovery_area/backup/backupsets/ora_df873523321_s46821_s1
./flash_recovery_area/backup/backupsets/ora_df873515765_s46811_s1
./flash_recovery_area/backup/backupsets/ora_df873520789_s46817_s1
./flash_recovery_area/backup/backupsets/ora_df873524162_s46823_s1
./flash_recovery_area/backup/backupsets/ora_df873518302_s46814_s1
./flash_recovery_area/backup/backupsets/ora_df873519953_s46816_s1
./flash_recovery_area/backup/backupsets/ora_df873516500_s46812_s1
./flash_recovery_area/backup/backupsets/ora_df873513413_s46809_s1
./flash_recovery_area/backup/backupsets/ora_df873514789_s46810_s1
./oradata/epps/invsubmat_d08.dbf
./oradata/epps/gmtinv_d08.dbf
./oradata/epps/gmtinv_x01.dbf
./oradata/epps/undotbs02.dbf
./oradata/epps/gmtinv_d07.dbf
./oradata/epps/undotbs01.dbf
./oradata/epps/gmtinv_x02.dbf

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文件的文件名称，但是对文件的信息（例如，文件大小、文件属性）一无所知，那么能否更详细显示一些文件属性或信息呢，当然可以，如下所示

[root@getlnx01 u03] 
-rw-r----- 1 oracle oinstall 2782846976 Mar  6 11:51 ./flash_recovery_area/backup/backupsets/ora_df873513413_s46809_s1
-rw-r----- 1 oracle oinstall 1878433792 Mar  6 11:53 ./flash_recovery_area/backup/backupsets/ora_df873514789_s46810_s1
-rw-r----- 1 oracle oinstall 1378492416 Mar  6 11:54 ./flash_recovery_area/backup/backupsets/ora_df873515765_s46811_s1
-rw-r----- 1 oracle oinstall 1641381888 Mar  6 11:56 ./flash_recovery_area/backup/backupsets/ora_df873516500_s46812_s1
-rw-r----- 1 oracle oinstall 1564065792 Mar  6 11:58 ./flash_recovery_area/backup/backupsets/ora_df873517396_s46813_s1
-rw-r----- 1 oracle oinstall 1663492096 Mar  6 12:00 ./flash_recovery_area/backup/backupsets/ora_df873518302_s46814_s1
-rw-r----- 1 oracle oinstall 1368244224 Mar  6 12:02 ./flash_recovery_area/backup/backupsets/ora_df873519197_s46815_s1
-rw-r----- 1 oracle oinstall 1629069312 Mar  6 12:04 ./flash_recovery_area/backup/backupsets/ora_df873519953_s46816_s1
-rw-r----- 1 oracle oinstall 1629954048 Mar  6 12:06 ./flash_recovery_area/backup/backupsets/ora_df873520789_s46817_s1
-rw-r----- 1 oracle oinstall 1202192384 Mar  6 12:07 ./flash_recovery_area/backup/backupsets/ora_df873521714_s46818_s1
-rw-r----- 1 oracle oinstall 1189388288 Mar  6 12:10 ./flash_recovery_area/backup/backupsets/ora_df873522876_s46820_s1
-rw-r----- 1 oracle oinstall 1089257472 Mar  6 12:11 ./flash_recovery_area/backup/backupsets/ora_df873523321_s46821_s1
-rw-r----- 1 oracle oinstall 1097687040 Mar  6 12:12 ./flash_recovery_area/backup/backupsets/ora_df873523646_s46822_s1
-rw-r----- 1 oracle oinstall 1051009024 Mar  6 12:13 ./flash_recovery_area/backup/backupsets/ora_df873524162_s46823_s1
-rw-r----- 1 oracle oinstall 4294975488 Apr  3 15:07 ./oradata/epps/gmtinv_d07.dbf
-rw-r----- 1 oracle oinstall 4194312192 Apr  1 22:36 ./oradata/epps/gmtinv_d08.dbf
-rw-r----- 1 oracle oinstall 4294975488 Apr  3 15:54 ./oradata/epps/gmtinv_x01.dbf
-rw-r----- 1 oracle oinstall 4294975488 Apr  3 15:57 ./oradata/epps/gmtinv_x02.dbf
-rw-r----- 1 oracle oinstall 4294975488 Apr  1 22:35 ./oradata/epps/invsubmat_d08.dbf
-rw-r----- 1 oracle oinstall 8589942784 Apr  4 09:55 ./oradata/epps/undotbs01.dbf
-rw-r----- 1 oracle oinstall 8589942784 Apr  4 09:15 ./oradata/epps/undotbs02.dbf

clip_image002

文件，并显示查找出来文件的具体大小，可以使用下面命令

[root@getlnx01 u03] 
1.3G    ./flash_recovery_area/backup/backupsets/ora_df873519197_s46815_s1
1.1G    ./flash_recovery_area/backup/backupsets/ora_df873523646_s46822_s1
1.2G    ./flash_recovery_area/backup/backupsets/ora_df873521714_s46818_s1
1.2G    ./flash_recovery_area/backup/backupsets/ora_df873522876_s46820_s1
1.5G    ./flash_recovery_area/backup/backupsets/ora_df873517396_s46813_s1
1.1G    ./flash_recovery_area/backup/backupsets/ora_df873523321_s46821_s1
1.3G    ./flash_recovery_area/backup/backupsets/ora_df873515765_s46811_s1
1.6G    ./flash_recovery_area/backup/backupsets/ora_df873520789_s46817_s1
1004M   ./flash_recovery_area/backup/backupsets/ora_df873524162_s46823_s1
1.6G    ./flash_recovery_area/backup/backupsets/ora_df873518302_s46814_s1
1.6G    ./flash_recovery_area/backup/backupsets/ora_df873519953_s46816_s1
1.6G    ./flash_recovery_area/backup/backupsets/ora_df873516500_s46812_s1
2.6G    ./flash_recovery_area/backup/backupsets/ora_df873513413_s46809_s1
1.8G    ./flash_recovery_area/backup/backupsets/ora_df873514789_s46810_s1
4.1G    ./oradata/epps/invsubmat_d08.dbf
4.0G    ./oradata/epps/gmtinv_d08.dbf
4.1G    ./oradata/epps/gmtinv_x01.dbf
8.1G    ./oradata/epps/undotbs02.dbf
4.1G    ./oradata/epps/gmtinv_d07.dbf
8.1G    ./oradata/epps/undotbs01.dbf
4.1G    ./oradata/epps/gmtinv_x02.dbf

clip_image003

文件大小做一个排序，那么可以使用下面命令

[root@getlnx01 u03] 
1004M   ./flash_recovery_area/backup/backupsets/ora_df873524162_s46823_s1
8.1G    ./oradata/epps/undotbs02.dbf
8.1G    ./oradata/epps/undotbs01.dbf
4.1G    ./oradata/epps/invsubmat_d08.dbf
4.1G    ./oradata/epps/gmtinv_x02.dbf
4.1G    ./oradata/epps/gmtinv_x01.dbf
4.1G    ./oradata/epps/gmtinv_d07.dbf
4.0G    ./oradata/epps/gmtinv_d08.dbf
2.6G    ./flash_recovery_area/backup/backupsets/ora_df873513413_s46809_s1
1.8G    ./flash_recovery_area/backup/backupsets/ora_df873514789_s46810_s1
1.6G    ./flash_recovery_area/backup/backupsets/ora_df873520789_s46817_s1
1.6G    ./flash_recovery_area/backup/backupsets/ora_df873519953_s46816_s1
1.6G    ./flash_recovery_area/backup/backupsets/ora_df873518302_s46814_s1
1.6G    ./flash_recovery_area/backup/backupsets/ora_df873516500_s46812_s1
1.5G    ./flash_recovery_area/backup/backupsets/ora_df873517396_s46813_s1
1.3G    ./flash_recovery_area/backup/backupsets/ora_df873519197_s46815_s1
1.3G    ./flash_recovery_area/backup/backupsets/ora_df873515765_s46811_s1
1.2G    ./flash_recovery_area/backup/backupsets/ora_df873522876_s46820_s1
1.2G    ./flash_recovery_area/backup/backupsets/ora_df873521714_s46818_s1
1.1G    ./flash_recovery_area/backup/backupsets/ora_df873523646_s46822_s1
1.1G    ./flash_recovery_area/backup/backupsets/ora_df873523321_s46821_s1

clip_image004

显示，这样就能解决这个问题。到这里，这个在Linux系统查找大文件的命令已经非常完美了，当然如果你还有很多的需求，那么可以在这个命令上做修改、调整.

clip_image005

2: 如何查找Linux下的大目录

文件的增长，那么我需要快速的了解哪些目录变得比较大，那么此时我们可以借助du命令来帮我们解决这个问题。

[root@getlnx01 u03] 
16K     ./lost+found
33G     ./flash_recovery_area
37G     ./oradata
70G     .

文件夹，那么可以将参数max-depth=2 ，如果你想对搜索出来的结果进行排序，那么可以借助于sort命令。如下所示

[root@getlnx01 u03] 
3.5G    ./flash_recovery_area/EPPS
16K     ./lost+found
29G     ./flash_recovery_area/backup
33G     ./flash_recovery_area
37G     ./oradata
37G     ./oradata/epps
70G     .
[root@getlnx01 u03]
1       ./lost+found
3527    ./flash_recovery_area/EPPS
29544   ./flash_recovery_area/backup
33070   ./flash_recovery_area
37705   ./oradata
37705   ./oradata/epps
70775   .

clip_image006

搜索出来的结果太多了（譬如，我从根目录开始搜索），一直在刷屏，如果我只想查出最大的12个文件夹，怎么办呢？此时就要借助head命令来显示了

[root@getlnx01 /] 
407480  .
167880  ./u04
158685  ./u02/oradata
158685  ./u02
152118  ./u04/oradata
70775   ./u03
37705   ./u03/oradata
33070   ./u03/flash_recovery_area
5995    ./u01/app
5995    ./u01
3551    ./usr
1558    ./usr/share
[root@getlnx01 /]#

clip_image007

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