Differences between version 13 and predecessor to the previous major change of Inode.
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| Newer page: | version 13 | Last edited on Wednesday, January 28, 2009 10:02:19 am | by AristotlePagaltzis | Revert |
| Older page: | version 12 | Last edited on Monday, June 4, 2007 2:01:36 pm | by BenStaz | Revert |
@@ -1,42 +1,5 @@
-An inode stores basic information about a regular file, directory, or other file system object. It contains a list of direct, indirect, and doubly and triply indirect pointers. On some FileSystems, very small files can be stored directly in the [Inode] itself.
+An inode stores basic information about a regular file, directory, or other file system object: permissions, ownership information, various timestamps, the size of the file, extended attributes, etc
. It also
contains a list of direct, indirect, and doubly and triply indirect pointers to the location of the actual file contents on disk
. On some FileSystems, very small files can be stored directly in the [Inode] itself.
-The inode number is a unique
integer assigned to
the device upon
which it
is stored. All files
are hard links
to inodes. Whenever a program refers to a file by name, the system conceptually uses the filename to search for the corresponding inode.
+However, __no filename__ is stored in the inode. Instead, filenames are stored in the contents of directories along with inode numbers.
The inode number is an
integer that is unique within
the FileSystem on
which the file
is stored. All filenames
are HardLink~s
to inodes. Whenever a program refers to a file by name, the system conceptually uses the filename to search for the corresponding inode. You can use "<tt>ls -i</tt>" to find out the inode number for a file and the stat(1) command to view all sorts of inode data about a file
.
-Sophisticated FileSystems create [Inode]s on demand, but with most, the number of [Inode]s on a [Partition] has to be decided on during FileSystem creation. It is rare to run out of [Inode]s unless you have an unusual usage profile such as storing a news spool or [Squid] cache. Exhaustion of the inodes will prohibit the creation of additional files even if sufficient HDD space
exists.
-
-!!How
many Inodes do I have free?
-
-*df - i
-
-!!What information does an [Inode] store?
-
-Note : Inodes do NOT contain filenames.
-
-* The size of the file in bytes.
-* The file's physical location (the addresses of the blocks of storage containing the file's data on a HDD)
-* The file's permissions.
-* The Device ID
-* The User ID of the file's owner.
-* The Group ID of the file.
-* Timestamps (ctime
,mtime and atime). See [FileTimes]
-* A reference count telling how many hard links point to
the [Inode].
-
-!!View Inode Information for a particular file.
-
-For example [PhilMurray's|PhilMurray] famous macaroni and cheese recipe:
-
-verbatim
>
-$stat macaroni_and_cheese
-
- File: `macaroni_and_cheese'
- Size: 1965 Blocks: 8 IO Block: 4096 regular file
-Device: 305h/773d Inode: 2775423 Links: 1
-Access: (0644/
-rw-r--r--) Uid: ( 1000/ staz) Gid: ( 1000/ staz)
-Access: 2007-05-16 00:21:17.000000000 +1200
-Modify: 2007-05-16 00:21:16.000000000 +1200
-Change: 2007-05-16 00:21:16.000000000 +1200
-verbatim>
-
-!!How to obtain a file's [Inode] number
-
-*ls -i <file
>
+Sophisticated FileSystems create [Inode]s on demand, but with most, the number of [Inode]s on a [Partition] has to be decided on during FileSystem creation. It is rare to run out of [Inode]s unless you have an unusual usage profile such as storing a news spool or [Squid] cache. Exhaustion of the inodes will prohibit the creation of additional files even if otherwise
sufficient storage capacity
exists. To find out how
many inodes are available
, you can use
the "
<tt
>df
-i
</tt
>" command.
